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  • 201.
    Hagman, Henrik
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Boström, D.
    Lundberg, M.
    Backman, R.
    Alloy Degradation in a Co-firing Biomass CFB Vortex Finder Application at 880 °CManuscript (preprint) (Other academic)
  • 202.
    Hammarstedt, Peter
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Oljeanalyser i kvalitetssyfte2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This work is performed on behalf of Komatsu Forest in Umeå. A potential problem observed at the company's quality assurance department is silicon content that is seen in the results of forest machines hydraulic oil analysis. To gain a deeper knowledge of contaminants in hydraulic oil and better utilize data from oil analysis, documentation has been developed to better determine if the silicon content in the hydraulic oil is harmful. Two questions: What relationship has silicon with other available elements such as uptime, chemical elements, acid number, water content and viscosity? Is silicon a clear indicator of the ingress of contaminants from external environment? Since the hydraulic fluid composition has renewed the work has been focused on the analysis of the new oil. A situation analysis that provides information about previous work on the subject is completed. The result from analysing test data indicates no connection between the silicon and the presence of sand and dust in the hydraulic oil. The oil's water content and acidity are important indicators to monitor.

  • 203.
    Hammond, Viktor
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lyfthjälpmedel för fundament2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 204. Hansbo, Peter
    et al.
    Larson, Mats G.
    Umeå University, Faculty of Science and Technology, Department of Mathematics and Mathematical Statistics.
    Continuous/discontinuous finite element modelling of Kirchhoff plate structures in R3 using tangential differential calculus2017In: Computational Mechanics, ISSN 0178-7675, E-ISSN 1432-0924, Vol. 60, no 4, p. 693-702Article in journal (Refereed)
    Abstract [en]

    We employ surface differential calculus to derive models for Kirchhoff plates including in-plane membrane deformations. We also extend our formulation to structures of plates. For solving the resulting set of partial differential equations, we employ a finite element method based on elements that are continuous for the displacements and discontinuous for the rotations, using -elements for the discretisation of the plate as well as for the membrane deformations. Key to the formulation of the method is a convenient definition of jumps and averages of forms that are d-linear in terms of the element edge normals.

  • 205.
    Hansson, Martin
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Transient road simulation of the cooling system in heavy-duty trucks using KULI2016Independent thesis Advanced level (degree of Master (Two Years)), 300 HE creditsStudent thesis
  • 206.
    Hansson, Rasmus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energiutredning Brf Kruthornet2016Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
  • 207.
    Hassan, Mohamed Aidarus Nur Sheikh
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energianalys av en tankstation: En förstudie av vilka energieffektiviserande åtgärder som kan göras på bensinstationer2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

     

    This study was carried out on behalf of Umeå municipality and Vindeln municipality together with Nenet (Norrbotten Energy Agency) as well as with the help of Exergi B(y)rån to carry out the  energy mapping at a petrol station. Many petrol stations use a lot of energy due to electricity, heating, cooling and lighting.

    Petrol stations are an important part of the infrastructure, a central hub of today’s society. By mapping their energy the stations can become more energy efficient, save money and also save the environment. By promoting their own work on energy efficiency and by having information about sustainable transportation at the station they could and would inspire their customers.

    The aim of this thesis was to investigate a petrol station’s energy usage and see which measures that can be taken for efficient energy use as well as arising interest among other petrol station owners. Calculation of cost-benefits and what actions that can be taken also been included. This work also gives an indication on how future petrol stations will look like according to the owners of the stations.

    The result of the survey shows a clear picture of a high energy use of 1126 kWh/m2 and therefore there is a great potential of taking energy efficiency measures. The petrol station is using cooling system due to the heat generated from all installations which is higher than the heat loss which occurs through the climate shell, ventilation losses and air leakage. By switching to LED lights in the store, in refrigerators and in different signs the generated internal heat will decrease. It is important that the ventilation system is correctly optimized to prevent unnecessary losses both in heat and economically. Some of the proposed measures for energy efficiency are to install twilight relay/dimmer for inside lighting, motion sensors in the storage, using temperature control for the heating cable in the ground and roof & gutter de-icing cables.

    A major operation that can be done is to build an airlock in front of the entrance for the front door as well as adding extra insulation to the attic.

    A major overview and renewal of the building installations is recommended, taking advantage of synergy in cooling and heating demands.

  • 208.
    Hasselrot, Rasmus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Investigation and evaluation of high-rise buildings in IDA ICE: A comparative study of energy efficient residential high-rise buildings in different climates2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is part of the major EU project EE-Highrise. The main objective of the EU project is to investigate high-rise buildings in different climates considering energy use, sustainability and cultural and economic differences in different countries. A demo high-rise building has been built in the capital of Slovenia.

    The purpose of this thesis was to build a model of the demo building in the simulation program IDA Indoor Climate and Environment. The model’s energy performance was then to be simulated in three different regions: Scandinavia, Central Europe and in the Mediterranean. Improvements to the climate shell and the ventilation system were to be examined and the results were then to be compared to European and Swedish Passive House certification schemes.

    A model was built in the simulation program IDA Indoor Climate and Environment according to the provided drawings of the demo building in Slovenia. Most of the building’s parameters were provided by the project group in Slovenia. When specific parameters were missing or difficult to motivate, standardized values were assumed. The model was modified into five cases: the base case, increased insulation of the external walls, improved glazing and frames for the windows, increased effective heat recovery efficiency and a combination of the energy saving measures. The model’s energy performance was then simulated at five different locations: Naples in Italy, Ljubljana in Slovenia, Malmo in southern Sweden, Karlstad in the middle of Sweden and Kiruna in the northern Sweden.

    When comparing the results to the requirements for the European Passive House certification, none of the investigated cases met the requirements due to a too large primary energy demand. However, if the requirement regarding the primary energy demand were to be disregarded, then the building in Slovenia would pass the requirements with an increased effective heat recovery efficiency for the ventilation system. Also the building in southern Sweden would pass the requirements with a combination of increased insulation for the external walls, improved windows and increased effective heat recovery efficiency.

    The Swedish Passive House certification would be fulfilled for the models in Malmo and Karlstad with an increased effective heat recovery efficiency, while the model in Kiruna did not pass the requirements. However, with a combination of the energy saving measures the model in Kiruna came very close to meeting the requirements.  

    The conclusion was that an increased effective heat recovery efficiency had the largest impact on the building’s space heating demand and that improving the windows increased the cooling demand in Naples by a large amount.

  • 209.
    Hasselstam, Jonas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Trafikverkets effektstyrningssystem - EFS 132 kV: Bidraget till minskade förluster2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The technological legacy from the early electrification of the Swedish railroads has resulted in a power grid with a lower grid frequency than the national power grid from which it is fed. Energy transfer between these power grids with different frequencies requires substations, adapting the grid frequency for the rail road power grid. For this purpose, a feeding power grid has been built, stretching across the country from Boden in the north to Tälle/Häggvik in the south.Power transfer in the Swedish power grid results in voltage angle differences which increase with increasing loads and transfer distance. These voltage angle differences are transferred from the power feeding substations to the rail road power grid, will in some extent cause loss of energy due to unwanted power flows from north to south.To minimize the losses due to this phenomenon, a power management system called EFS 132 kV has been developed and implemented. The system minimizes the unwanted power flows and controls the desired power flow for a good distribution of loads between the power feeding substations.This thesis investigates the extent of the transmission losses avoided due to the EFS 132 kV that coordinates the idling angles to a common reference point.The results indicate that EFS 132 kV affects the power flow, especially between the northern substations through an improved load distribution. The annual energy savings due to transfer losses are estimated at 24 GWh.The system’s power flows has been analyzed to detect weaknesses and losses and the opportunities and constraints facing a continued system improvement work.

  • 210. He, Hanbing
    et al.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Energy Engineering, Division of Energy Science, Luleå University of Technology, Luleå, Sweden.
    Öhman, Marcus
    Time-Dependent Crack Layer Formation in Quartz Bed Particles during Fluidized Bed Combustion of Woody Biomass2017In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 31, no 2, p. 1672-1677Article in journal (Refereed)
    Abstract [en]

    Bed agglomeration during combustion and gasification of woody biomass fuels in quartz beds has been frequently studied, and chemical mechanisms responsible for bed agglomeration have been suggested: However, few studies have focused on the bed material deposition on walls, in cyclones, and return legs in fluidized bed combustion. Part of these bed material depositions originates from sticky fragments of alkali-rich silicates formed after crack formation in older quartz bed particles. The crack layer formation in quartz bed particles in fluidized bed combustion of woody biomass was therefore investigated by collecting bed material samples of different ages from full-scale bubbling and circulating fluidized bed facilities. Scanning electron microscopy/energy-dispersive spectroscopy was used to analyze the crack morphology and composition of the layer surrounding the cracks. For quartz bed particles with an age of some days, a crack in the quartz bed particle was observed in connection to the irregular interface between the inner layer and the core of the bed particle. The crack layer composition is similar for quartz particles with different ages and for samples taken from different fluidized bed techniques. Their composition is dominated by Si, K, Ca, and Na (except O). These crack layers become deeper, wider, and more common as bed particle age increases. The crack layers eventually connect with each other, and the whole quartz particle is transformed into smaller quartz cores surrounded by crack layers, which were observed in particles older than 1 week. From the characterization work, a crack formation process including three phases is proposed on the basis of the presumption that the initial crack layer formation resulted from the presence of induced cracks in the inner quartz bed particle layer. Fragmentation after the third phase is likely responsible for the formation of sticky alkali silicate deposit formation, and a weekly complete exchange of the bed is therefore recommended to avoid problematic deposits in combustion of woody-type biomass in fluidized bed combustion.

  • 211.
    Hedayati, Ali
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering.
    Lindgren, Robert
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering.
    Ash transformation during single-pellet combustion of agricultural biomass fuels – focus on K and P2018Conference paper (Refereed)
  • 212.
    Hedlund, Tobias
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Parametriserad 3D-modell av cyklon: Parametrisering av en 3D-modell av ett cyklonfilter i SolidWorks för snabb framtagning av nya konstruktioner till Outotec Skellefteå2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis project has been executed at Outotec Sweden AB in Skellefteå. Outotecs main business focus is selling mineral and metal processing technologies. A rest product from the metal process is particle-polluted gas and cyclone designs are today the most commonly used abatement device for particle control. A cyclone provides a simple design with high efficiency particle percolation by using air streams.

    The purpose of this work is to reduce the time it takes create new cyclone designs in Outotecs projects. An extensive construction work is needed for every new cyclone order due to new designs. Therefore a parametric 3D-model of a cyclone is desired. The model has to be easy to use and quick to edit cyclone size and properties. From a previous project an existing 3D-model of a cyclone was used as a starting point to be revised and made parametric.

    A method called top-down modeling was used to make the model parametric in SolidWorks.  The top-down approach relates and defines the dimensions of each part to already existing components higher up in the assembly. In this model the cyclone gets its dimension values from a sketch-tree that is connected to variables in a equation table. The sketch-tree then drives the dimensions of all parts down through the cyclone assembly.

    Next, construction drawings connected to the 3D-model were created. These drawings automatically get updated when the model gets resized. A user guide was written to simplify the use of the model. The main priority to create a parametric 3D-model of a cyclone was successfully completed with a model that is easy to use, quick to resize and modify.

  • 213.
    Hedström, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ökad matarvattentemperatur vid biopannan Smurfit Kappa Piteå: Increased feedwater temperature at biomass boiler Smurfit Kappa Piteå2018Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [en]

    Smurfit Kappa Piteå is the largest kraftliner producer in Europe. At the mill they have five different steam producers and one of those is the biomass boiler, which is a steam boiler producing overheated steam at 120 bar and 520C. The purpose of this report is to investigate the possibilities to increase the feedwater temperature from today’s 180C to 210C. The consequences on the system are depending on the temperature in the different process stages and the process temperatures are therefore calculated via a method named The NTU-method which is a suitable method to analyze the heat transfer within an object when the ingoing and outgoing temperature are unknown. The feedwater is preheated with a heat exchanger that is heating the feedwater from 130C to 180C using steam with a pressure of 11 Bar. To increase the temperature to the desired  the approach is to install a complementary feedwater heater that uses steam with a pressure of 27 Bar. The new heater is supposed to heat the feedwater from 180C to 210C while the old heater takes the temperature from 130C to 180C. If the old heat exchanger approaches its end of life span it may have to be replaced with a new one with the same design data. One way to fulfill the required heating is to install one feedwater heater that takes the temperature from 130C to 180C using steam with a pressure of 11 Bar and in the next step install the second feedwater heater that takes the temperature from 180C to 210C using steam with a pressure of 27 Bar. There are two alternatives to installation of complementing high pressure heat exchanger. First alternative A is to install the second feedwater heat exchanger between the economizer and the steam dome. Second alternative B is to install the second feedwater heat exchanger between the already existent heat exchanger and the economizer. The consequence of the installation B is an increased energy loss due to the combustion gases while the consequence of installation A does not involve any increase in energy losses. Therefore, alternative A is wiser. However, whatever alternative that is chosen problem will arise since the temperature margin between the steam dome’s saturation temperature and incoming feedwater temperature needs to be at least 25C. This means that the largest possible pre-warming between the boiler’s workload 50-110% is 21C which not do apply to the whole interval. So, as it seems, the utilization of a second feedwater heat exchanger is not applicable over the whole interval of workloads. The increased feedwater temperature come with other consequences on the system. The whole system will be changed due to the increased temperature and it will affect the details. Some of the pipes must be replaced with new ones that fulfills the restrictions accompanying higher process temperatures. The purpose of the increased feedwater temperature is to increase the mass flow steam to the turbine. From calculations and the extraction-steam-consumption graph the increasing net power outcome from the turbine will increase with about 7.5% due to the increasing feedwater temperature. This will make the turbine produce even more electric energy and generate a bigger income to the factory. The investment cost is in total approximately 25MSEK, including replacing the old feedwater heater with a new one and installing a second feedwater heater. With a payback time of eight years and a life span of ten years it is necessary to question the economic potential of the installation. It provides a hint of the potential of the project. However, one should know that all numbers in this report are estimated from rough calculations. 

  • 214.
    Helin, Klas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Möjligheter och risker med miljöcertifieringssystemet Miljöbyggnad i en totalentreprenad: En ekonomisk optimering2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Environmental assessment for buildings is a means to reach the national environmental goals of Sweden. The construction and real estate sector accounts for a large part of Sweden's green house gas emissions and use of fuel, and environmental assessment tools can work as an incentive to improve on that. The Swedish tool Miljöbyggnad has grown considerably the last few years, and gives a solid option for the Swedish market. The tool assesses 16 indicators that are weighted together to give a building a final rating. The building can be rated Brons, Silver or Gold.

    The purpose of this study was to investigate and demonstrate risks and opportunities with the environmental assessment tool Miljöbyggnad, for both parties (the client and the contractor) in a design-build contract. This was accomplished by conducting a economic optimization of selected assessment tools indicators for a final rating of Silver, with the help of a reference building. From the result a methodology and general comprehension were acquired that can be applied in future construction projects. The aim of the study was to assess the reference building according to Miljöbyggnad's criteria. Then from the assessment present two optimal indicator configurations, one for the client and one for the contractor, that both yield a final grade of Silver.

    A model of the reference building was drawn using the architects drawings, and then built within an simulation software. Input for the simulations were mainly design instructions from the property owner of the reference building. Simulations and calculations to assess the building was conducted according to instructions from the Miljöbyggnad manual. From the result of the assessment, possibilities for optimization were investigated. A couple of actions were tested for their possibility to change the indicator grades, and differences in costs and pay-back times were calculated.

    The building was given a final grade of Miljöbyggnad Silver, where the indicator grades ranged from Bronze to Gold. In the optimal indicator configuration for the contractor, the grade of the indicator Heating demand was lowered from the original assessment. From the actions that were tested a saving opportunity was yielded from changing of the envelope, walls, roof and slab was worsened. In the optimal indicator configuration for the client, the grade of the indicator Energy use was increased and the grade of the indicator Energy sources was lowered. Saving opportunities were yielded from doing the same envelope changes but also improving windows, installing solar collectors and using Nordic electricity mix for appliance and building operation electricity.

    The conclusion from this study is that as a client to only demand a final grade for the building as part of the procurement is not recommended. A Miljöbyggnad certification with a design-build contract does not necessarily signify the most energy efficient building, there are distinct risks. Especially regarding the indicators within the area Energy in the assessment tool, and in practice the building's operating costs for energy. In a more controlled design-build contract with demands on specific indicators and even technical solutions, there are opportunities for the client to affect several indicator grades, as well as make cost savings.

  • 215.
    Henriksson Rapp, Magnus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Förslag på funktionstillägg till gripkran2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På ett område i underjordsgruvan LKAB i Kiruna finns en gripkran tillverkad av JTM Produkt AB. Den används för att plocka upp järnskrot som av misstag hamnat i de malmvagnar som transporterar sten från schakt till stenkrossar. När det har hamnat sten ovanpå järnskrotet går det inte att använda kranen till dess ändamål och det är ett problem.

    Syftet med det här projektet är att ta fram ett förslag på en ändring av kranen för att komma till bukt med problemet.

    Förutsättningarna för att genomföra konstuktionsförslaget har skapats i samråd med JTM Produkt och LKAB. Konstruktion och framtagning av ritningar har utförts på Umeå Universitet.

    Resultatet av arbetet blev ett konstruktionsförslag där man byter ut nuvarande rotator på gripkranen till en tiltrotator. Det medför att man kan få en grävande rörelse och mer precision i gripen.

  • 216.
    Hjalmarsson, Joakim
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Uppdate and improvement of the mains selectivity in Edsbyn & Ovanåker.2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    A power failure can lead to major financial losses for companies and industries. To prevent unnecessary power outages, selectivity of the mains relay protection is established. This means that the malfunctioning part is disconnected from the working network. Inadequate selectivity of the mains relay protection can also lead to personal danger, the equipment takes unnecessary damage and a major part of the power grid is affected by a minor fault. Electricity distribution companies therefore have selective plans where a summary is made of the short circuit currents and disconnection times for the relay protections in their own grid.

    Edsbyns Elverk AB is a privately-owned electricity company, currently owned by approximately 600 shareholders. The business consists of production, sales and distribution of electricity in an efficient manner, within the county of Edsbyn and Ovanåker.

    Development and changes to the electric grid means that updates must be made for the existing selective plan. This may lead to changes for the relay current and time settings. These types of changes will be highlighted during the work and possible solutions will be presented. This work has been done as a degree project for a bachelor’s degree in the field of energy engineering.

    The work shows that improved selectivity can be achieved for three of the eight outgoing electrical compartments, that if relay protection settings are changed and updated according to current operating conditions. Recommendations have been presented in charts where the settings of time and current have been drawn. These have been made for two conditions, recommended times and currents as well as previous settings. The result can then be compared and motivate a change for the old relay settings.

  • 217.
    Holma, Evert
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Designkoncept för standard hydraulik modul2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis has been conducted at Outotec in Skellefteå, Outotec is a Finnish company that supplies process and automation solutions for metal, mineral, energy and water industries.

     

    Hydraulics are included in many of Outotec's equipment’s and process solutions and because of this they have come to the idea of having a smaller hydraulic module for operating simple functions that use hydraulic cylinders. This thesis has been to develop a design concept for this small hydraulic module to operate the cylinders that are used to run simple functions in a metal melting plant.

     

    The work includes the development of a hydraulic diagram for the module where the necessary components are included, the calculation basis for selecting components to the module, a proposal on which significant and important components that can be used for the system and a design proposal on how the module might look at a completion.

     

    As a result of this, a decision basis was developed in order to complete the module. The decision data are based on calculations made on the components that will be needed in the module and the various functions that the module is supposed to run.

     

    The bigger components are selected and can be seen as a guideline for a final decision, so it is possible to choose a similar product but with other dimensions or products from another manufacturer. The result also includes a hydraulic diagram describing the function of the module and which components that should be included when the module is completed. A draft of the design and layout is designed for the module, this does not contain all the components, but the main components are included such as the tank, motor and accumulator.

  • 218.
    Holmberg Jonsson, Filip
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av vikthållare: Konstruktion av vikthållare och lagerlösning för skivstänger2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this bachelor thesis, a design on a series of weightholders has been developed. The work is carried out on behalf of the company Balticfitness, who has an interest for starting their own production of barebells. These barebells are supposed to compete with other manufacturers on the market. Since this work isn’t a new idea, the work being presented in this report will be based on a market research and dialogues with experts in these areas. The parts and drawings presented in this work have been produced using the CAD software SolidWorks. In the business of barebells and weightholders there are variety of standards that must be kept in order for these barebells to be classified for competitions which have been the frame for this work. The project has delivered a result in which a number of parts and a finished result have been developed. The employer Lars Norberg may with the results which have been produced based on this work, find a suitable manufacturer and start his own production.

  • 219.
    Holmgren, Per
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Entrained flow studies on biomass fuel powder conversion and ash formation2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Reducing the global dependence on fossil fuels is of paramount importance in tackling the environmental challenges we face, not only tomorrow, but already today. Biomass offers a renewable supply of CO2-neutral raw material that can be converted into many different forms of fuels and valuable chemicals, making it a prime candidate for the technologies of tomorrow. However, the heterogeneous nature and distinctly different elemental composition of biomass compared to traditional fossil sources present new challenges to be solved. When it comes to thermochemical technologies, key issues concern fuel conversion efficiency, ash formation, ash/fuel interactions and ash/reactor material interactions.

    The objective of the present thesis was to provide new knowledge and insights into thermochemical fuel conversion, in particular its application in entrained flow technologies. A laboratory-scale reactor was constructed, evaluated and was used to study several aspects of high-temperature entrained flow biomass fuel conversion. Pulverized fuel particles from different biomass sources were used, and their physical and chemical interactions with the surrounding atmosphere, the concurrent ash element release, ash formation, and phase interactions were also studied in detail. In addition to the entrained flow reactor designed and constructed for this purpose, the main method for data collection was in situ optical studies of converting particles, either while entrained in the flow or when impacting upon surfaces. Elemental composition analysis of collected samples and gas analysis were also performed, allowing for a deeper understanding of ash element fractionation and interactions and thus explaining the observed properties of the resulting deposits or slag.

    The degree of conversion of fuels with very low ash content, such as stem wood, was well described and modeled by a novel method using optical data, offering a non-intrusive and non-destructive alternative to traditional techniques. Coupling computational fluid dynamics with optical data allowed for improved experimental data interpretation and provided improved accuracy for fuel particle residence time estimations, which is an important parameter when studying fast chemical reactions such as those taking place in reactors for entrained flow conditions. The results from studies on ash formation gave new insights into the feasibility of using dry-mixed K-rich additives for improving slag properties during gasification of Ca-rich and Si-rich fuels. Interpretations of the experimental results were supported by thermodynamic equilibrium calculations, and the conclusions highlight both possibilities and challenges in gasification with high fuel flexibility while at the same time producing a flowing slag. Applications and future implications are discussed, and new topics of interest are presented.

  • 220.
    Holmgren, Per
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Slag Formation during Entrained Flow Gasification: Silicon Rich Grass Fuel with KHCO3 Additive2018In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, no 10, p. 10720-10726Article in journal (Refereed)
    Abstract [en]

    Prediction of ash particle adherence to walls, melting, and flow properties are important for successful operation of slagging entrained flow gasifiers. In the present study, silicon-rich reed canary grass was gasified at 1000 and 1200 °C with solid KHCO3 added at 0, 1, or 5 wt % to evaluate the impact and efficiency of the dry mixed additive on slag properties. The fuel particles collided with an angled flat impact probe inside the hot reactor, constructed to allow for particle image velocimetry close to the surface of the probe. Ash deposit layer buildup was studied in situ as well as ash particle shape, size, and velocity as they impacted on the probe surface. The ash deposits were analyzed using scanning electron microscopy–energy-dispersive X-ray spectroscopy, giving detailed information on morphology and elemental composition. Results were compared to thermodynamic equilibrium calculations for phase composition and viscosity. The experimental observations (slag melting, flow properties, and composition) were in good qualitative agreement with the theoretical predictions. Accordingly, at 1000 °C, no or partial melts were observed depending upon the potassium/silicon ratio; instead, high amounts of additive and a temperature of at least 1200 °C were needed to create a flowing melt.

  • 221.
    Holmgren, Per
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå Universitet.
    Carlborg, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå Universitet.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå Universitet.
    Slag Formation During Entrained Flow Gasification: Calcium Rich Bark Fuel with KHCO3 AdditiveManuscript (preprint) (Other academic)
    Abstract [en]

    Managing slag properties is of utmost importance for successful operation of entrained flow gasifiers. The present study details some aspects of slag formed from a softwood bark fuel, and especially the situation with only small amounts of mineral contaminants, meaning composition is shifted from Si- towards P-dominated ash. Wood bark with and without KHCO3 additive was gasified between 850 °C and 1300 °C at O2 stoichiometric ratio (λ) 0.6 to study the resulting ash properties and the influence of the additive. The ash particles collided with a flat impact probe inside the hot reactor, with particle impact angles varied between 90° to 30°. The reactor and probe were constructed to allow for long-distance microscope data collection close to the surface of the probe. In situ PIV and SEM-EDS of deposit samples from lab scale entrained flow gasification experiments were used for evaluation, while XRD was used to characterize carbonates. High potassium release was found but numerous spherical ash particles indicated lower ash melting temperatures than expected from the bulk ash composition. These new findings propose a mechanism for melt formations involving carbonates rich in potassium and phosphorous, followed by K-release and calcination leading to solidification.

  • 222.
    Holmlund, Karolina
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Okonventionella lösningar på solcellsproblematiken: Unconventional solutions of problems caused by photovoltaic cell2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Det svenska elnätet har i dagsläget en mycket hög leveranssäkerhet, men står inför en stor utmaning i och med decentraliseringen av elproduktionen. Allt fler privatpersoner och företag upptäcker fördelarna med att producera egen el i direkt anslutning till fastigheten. När solcellsanläggningar ansluts till elnätet ställs nya krav på nätet och dess distributionsmöjligheter. Främst skapas överspänningar när el distribueras från solcellsanläggningarna och ut på lågspänningsnätet. Detta examensarbete utreder vilka okonventionella lösningar som är tekniskt möjliga att implementera på marknaden för att möta den nya problematiken. Projektet innefattar en jämförelse mellan de okonventionella lösningarna och de två lösningar som rekommenderas i dagsläget, batterilager och ombyggnationer av det befintliga elnätet.

    För att besvara projektets frågeställningar har en litteraturrapport skrivits med grund i gällande regelverk, genomförda projekt och nya tankar och idéer från kunniga inom området. För- och nackdelar med de två rekommenderade lösningarna sammanställdes utifrån befintlig teknik innan de okonventionella lösningarna utreddes. Delvis saknas ekonomiska jämförelser för alla okonventionella lösningar, vilket beror på bristande tekniska specifikationer eller idéer utan praktisk grund. Projektet är avgränsat till landsbygdsnätet eftersom det i regel är svagare än stadsnätet och de nätanslutna solcellsanläggningarna påverkar i större utsträckning de svagare näten.

    Fem okonventionella lösningar omnämns i rapporten. Den förstnämnda lösningen berör växelriktarna som finns i anslutning till solcellsmodulerna. Där det främst handlar om ett begränsat effektuttag eller produktion och konsumtion av reaktiv effekt. Därefter utreds vilken potential smarta hem och smarta elnät har. Konstateras att det kräver höga implementeringskostnader och omfattande ombyggnationer av elnät och fastigheter. Den tredje lösningen berör huruvida lindningskopplarna vid transformatorerna kan användas för att lösa den nämnda problematiken. Den fjärde tänkbara lösning som i dagsläget redan testas ute på elnätet är 1 kV-system som kortfattat går ut på att höja spänningen från 0,4 kV till 1 kV. Det medför en ökad tolerans mot överspänningar och öka överföringskapaciteten på nätet. Slutligen lyfts idéer gällande spänningsreglering på lågspänningsnätet med kraftelektronik.

    De nämnda lösningarna har tekniskt sett potential att etableras på marknaden, men i flera fall blir implementeringskostnaderna höga. Dessa lösningar skulle fördelaktigt testas på elnätet för att utvärdera i vilken utsträckning de kan lösa problematiken och vilka konsekvenser det medför.

    The full text will be freely available from 2020-01-01 00:00
  • 223.
    Hu, Yiru
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Effektivisering av spannmålspackning2018Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Idag torkas de mesta spannmålen före lagring, dock påverkar utomhusklimatet kvalitén. I värsta fall måste spannmålen torkas med energikrävande metoder som leder till högre energi-, tid- och arbetskostnad. Krossensilering är ett sätt att lagra spannmål med högre vattenhalt. Detta lagringssätt kan sänka kostnader, dock passar det bäst för större lantbruk. I ett tidigare projekt konstruerades en spannmålspackningsenhet med stående säck, men maskinen är för hög så den behöver fler maskiner för att hjälpa till att fylla på spannmål, och har låg packningskapacitet.

    För att ta fram ett förändringsförslag genomförs en undersökning på den befintliga utrustningen. De mätdata som erhållits under arbetsgång visar hur hårt spannmålen kan packas med skruv och cylinder och hur trycket fördelas i säcken. Två förslag har tagit fram för att lösa den befintliga maskinens problem. Förslag 1 är att bygga ytterligare en ny testrigg och återvinna stativet. Förslag 2 är att bygga en ny packningsenhet med liggande säck, och att återanvända skruven. Efter noggrann jämförelse väljs förslag 2 eftersom det uppfyller alla krav som ställt i projektet.

    Denna rapport är en del av ett EU projekt- Wet Grain in Package som ekonomiskt stöds av bland annat Interreg Botnia- Atlantia. Mer information om projekt finns i bilaga 1. Arbetet är genomfört på RISE SMP Svensk Maskinprovning AB (SMP) i Umeå.

  • 224.
    Hussein, Gomil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energiförluster i eternitkulvert och flödeskartläggning av Kramfors fjärrvärmenät2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Kramfors heating network was built in the 1960s. Culverts that were used at the time were composed of a pipe of steel, asbestos cement (eternite) and polyurethane foam (PUR foam) blown with chlorofluorocarbons gas (CFC gas) as insulation. The expansion of district heating began during the 1970s and 1980s and even more in 1990s. One problem that may arise during expansion of a district heating network is the risk of overloading the main pipes of the heating network if they were designed for lower flows.

    The aim of this work is to calculate energy losses from eternite culvert over a twelve months period to then compare losses, both financially and from an energy perspective, with today culvert as a reference. Even a flow mapping on the network will be presented for the month of December 2012 as a basis for future growth of subscriber stations.

    Eternit culvert energy losses was more than twice as much as the losses with modern culvert for the reason that the heat conductivity in the eternit culvert is about 3 times higher compared with modern culverts.

    If Neova has to supply the entire investment, the analysis shows that if the price of the fuel and the energy losses is constant throughout the payoff time it would take 104 years for the investment to pay off.

  • 225.
    Hägg, Linus
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Mätning och modellering av lufthastigheten i virkestorkar2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Wood drying is the most energy-intensive process at a sawmill and air circulation fans are a samills largest consumer of electrical power. Increasing prices for electrical power and increased environmental awareness makes it interresting to investigate if the consumption of electrical power during drying can be reduced without riskning the quality of the dried timber. To accomplish this, information about the velocity distribution within the kiln is vital.

    In this thesis 20 hot film anemometers were used to measure the air velocity in an intustrial batch kiln. The flow was also simulated in a reduced 2D-model. Due to limitations of the anemometers the measurements were conducted on already dried boards.

    The results show that the flow is relatively more homogenous at higher velocities. This indicates that drying conditions vary more between different locations within the kiln when the air speed is reduced. The simulations and measurements show that as much as 30 % of the flow is not activley involved in the drying processs, because it passes through the larger bolster spaces between packages. When the seal between timber stack 2 and the dryers right wall was removed no significant difference in air flow distribution was measured.

  • 226.
    Häggkvist, Ylva
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivisering i Stigbygeln: En förstudie2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Diös fastigheter is Northern Sweden's largest private real estate company. The bulk of the company's holdings constists of centrally located retail, industrial and office buildings, 23 of which are located in Umeå. Diös fastigheter works continuosly to decrease energy consumption in their building stock. One part of this work is to pursue the Greenbuildning environmental certification for buildings. This paper examines a building named Stigbygeln 2, situated on Dragonfältet i Umeå, currently rented by the logistics company PostNord. The energy consumption last year was approximately 290 kWh per square meter. This paper examines the reasons for the high energy consumption and which measures to increase energy-efficiency yield the largest energy-savings at the lowest cost.

     

    At the present time Stigbygeln 2 is connected to the municipal district heating network, and distric heating is utilized as heating source to warm the inlet air of the ventilation system, which in turn warms a significant portion of the facilities found in the building. Heating of supply air constitutes 85% of the total heat load, and there is no system for heat recovery.

     

    Stigbygeln has been constructed in the simulation tool IDA ICE in accordance with known conditions, and different measures to increase efficiency have been investigated, individually as well as combined. Through LCC analysis, savings resulting from decreased energy consumption have been weighed against the initial investment cost and the operational cost.

     

    The result shows that a switch to FXT ventilation would yield the largest energy savings, 57%, and that this is also the financially most advantageous route. Conversion to geothermal heating reduces energy consumption by 37%, but is not economically viable. A swith to LED lighting is a measure that yields a good return on the investment cost and lowers energy consumption by 7%. The savings are greatest when a change of ventilation system is combined with a change to LED lighting.

  • 227.
    Hägglund, Hampus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektiviseringsförslag på Knorthems avloppsreningsverk: En förstudie till förslag som kan leda till minskad energianvändning på Knorthems avloppsreningsverk2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Wastewater treatment plants fulfill an important function in a society adapted to eco-cycle. The water used and polluted by human must be purified from substances that lead to eutrophication, oxygen deficiency and littering in our seas and oceans. The water cleaning process is an energy guzzler in our society. Many plants are built in the 70s and 80s and old equipment is still used. A more efficient process means that less external energy in the form of heat and electricity need to be bought, which is a cost saving that can make investments viable for the long term. It can also be seen in line with EU environmental work on 20% more efficient energy use by 2020.

    The work for this report is made on the Knorthems wastewater treatment plant in Central Örnsköldsvik, where water from Örnsköldsvik Centre is purified. The cleaning process can be divided into two stages. The first is to purify the water so it can be discharged into Örnsköldsviksfjärden, and the second step is to digest the sludge from the water purification. The digestion process produces biogas fired to heat up sludge in the digestion tank and keep it at 37.5℃ and heat up the buildings.

    The purpose of this work has been to develop suggestions how the energy use can be reduced at the treatment plant. To get a picture of the energy distribution, a theoretical survey is made over electricity need in the process and building, as well as the heating needs of buildings and process. Because of the limited time, only the major electricity users were accurately calculated and analyzed. Other equipment has been checked and electricity users effect and operation time have been used in the estimation of used energy. The warming goes to premises for the staff and process, as well as heating and keep the sludge in the digestion tank warm. The heat flow for warming the buildings was measured and an equation was developed to determine the relationship between the outside temperature and heating requirement. Calculations of energy used for heating of the buildings could then be done. The digestion tanks heating could be calculated based on the fed of sludge and the heat losses through the tank. By demand a construction model of the digestion tanks the heat losses could be calculated.

    The results of the energy survey has been used as a basis for further work with suggestions for changes that will lead to reduced energy use. The result of the suggestions includes both simple changes to adjust the operation of ventilation and inspection of the radiators, to bigger suggestions such as heat exchange between sludges and the renovation of the aeration basin air system.

    During the work many assumptions and simplifications have been made to achieve the results. Only a few measurements have been executed during the very short periods of time and then served as the basis to calculate the energy in one year. This makes that the presented values are rough theoretical calculations and should be used as an indication of where further and deeper works can be done.

  • 228.
    Hägglund, Jonas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Järnvägsgrip: Design av en grip anpassad för järnvägsarbeten med grävlastare2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 229.
    Häggström, Gustav
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Evaluation of the potential for co-gasification of black liquor and biofuel by-products: An experimental study of mixing and char reactivity2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The increased use of fossil fuels during the last centuries has caused elevated levels of carbon dioxide in the atmosphere. There is significant evidence that this is the cause of global warming. To mitigate the global warming, measures has to be taken to use renewable fuels and make processes more efficient.

    Catalytic gasification and downstream upgrading of synthesis gas is a promising technology for biofuel production, where previous research in black liquor gasification is currently expanding into a wider fuel feedstock.

    This work focuses on co-gasification of black liquor and by-products from other biofuel production technologies. The interesting by-products were crude glycerol from biodiesel production and spruce fermentation residue from ethanol production. The main goals were to study if the fuels can mix homogeneously and study the char reactivity. CO2 char gasification for mixtures of black liquor and glycerol or fermentation residue respectively was studied using thermogravimetric analysis (TGA) for four temperatures between 750°C and 900°C.

    The results show that glycerol can be mixed in all proportions with black liquor and indicate that the char reactivity is unchanged. The sustained char reactivity for blends is attributed to the volatility of glycerol. The fermentation residue does not produce a homogeneous mixture with black liquor and the char is less reactive.

    More studies should be performed to further elucidate the validity of the results.

  • 230.
    Häggström, Gustav
    et al.
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering.
    Wagner, Katharina
    Bioenergy 2020+ GmbH, Wienerstraße 49, A-7540 Güssing, AustriaInstitute of Chemical, Environmental & Bioscience Engineering, TU Wien, Getreidemarkt 9/166, A-1060 Vienna, Austria.
    Kuba, Matthias
    Bioenergy 2020+ GmbH, Wienerstraße 49, A-7540 Güssing, AustriaInstitute of Chemical, Environmental & Bioscience Engineering, TU Wien, Getreidemarkt 9/166, A-1060 Vienna, Austria.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering.
    Effect on P-mineralization in fluidized bed combustion of chicken litter with wheat straw and bark residues2018Conference paper (Refereed)
  • 231.
    Häreskog, Linnea
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Integration of hydrothermal processes on a forest-based biorefinery site2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The pulp and paper industry (PPI) is a business that produce large amounts of residues annually. Besides bark, large quantities of sludge are produced from the various parts of the industrial process. The sludge that comes from the biological wastewater purification process is denoted biosludge and is known as a particularly problematic waste product. It is of interest to reduce the amount of sludge from the PPI or to find new ways of handling the produced sludge. The common way to treat the PPI sludge is by incineration in the site’s bark boiler. The material is however difficult to dewater and often does more harm than good in the boilers. Different technologies to try and dewater the sludge further have been investigated previously, one that has recently been noted is hydrothermal treatment. The technology described in this thesis work is called hydrothermal carbonization (HTC) which uses water as a reaction media to turn the sludge into a coal-like material called hydrochar. The hydrochar has a higher heating value than the initial sludge and is more hydrophobic which makes it easier to dewater.

    This Master’s thesis describes the process technologies of the HTC process and presents some of the recent work done within the area. The properties of different residues from the PPI are presented before the integration of an HTC process on the biorefinery site in Domsjö, Sweden is discussed using previously published articles. A survey concerning sludge from industries within a 500 km range of the Domsjö biorefinery site is made to investigate whether residual streams similar to the ones at the Domsjö site are available in the vicinity.

    The results show that an HTC process demands energy in the form of steam and/or electricity. A previously made pinch and total site analysis show that the most accessible steam at the Domsjö biorefinery site, that most appliances and process steps uses, is at 7 bars. There are also steam levels of 20 and 32 bar in the area, which is within the range an HTC plant requires. The HTC process water demands further treatment which puts an extra stress on the already existing water purification process. The Domsjö biorefinery site produces 6000 tonnes of biosludge per year. Several HTC companies produce units that normally treat 20000-50000 tonnes of sludge per year, which indicates that additional sludge could be added to reach full capacity. The survey shows that there are similar materials available in the surroundings. It is concluded that further investigations concerning the sludge materials must be made before real implementation consequences can be calculated.

  • 232.
    Högberg, Jesper
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energisimulering för ett flerbostadshus: Undersökning av energianvändning med hjälp av IDA ICE2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In recent years, it has been found that a greater understanding of the existing building stock's energy use has become increasingly important and that it must be made more energy efficient if we are to achieve all our set goals. If you look at today's energy use, the housing and services sector accounts for about 40% of Sweden's total energy consumption. If you look specifically at the multi-dwelling houses, these constitute approximately 30% of the energy use. Therefore, it may be important to get information about what measures can be taken to reduce energy use. 

    The purpose of the project is to produce proposals for measures that reduce the energy consumption of a multi-dwelling house located in Umea built in 2006.

    The energy simulation program IDA ICE has been chosen to build a model of the multi dwelling house. When the building has been created in the program, the simulated apartment house will be compared with a real energy declaration that was carried out in 2009, this is done because it is a strong source that makes the project more credible. When the energy declaration values ​​and the simulated values ​​match, the project goes on to find different energy-efficient measures. The energy efficiency that will be simulated in IDA ICE is the replacement of existing ventilation system to an FTX system with higher heat recovery, some other energy efficiency proposals that will be made are the lowering of the indoor temperature from 22 degrees Celsius to 20, it will also be tested to additionally insulate the outer walls with mineral wool. and to replace existing windows with a better U-value. The solution that turns out to be good is to replace the existing FTX system with heat pipe against an FTX system with rotary heat exchanger with an efficiency of 85% then you will save 76 270 kWh or 17,4 kWh/m2 this will be a saving of 50 338 SEK/year.

  • 233.
    Högström, Isak
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Förskolan Hoppet2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete uppförts i samarbete med VVS konsulterna Skellefteå. Det behandlar en jämförelse av ventilationssystem på en förskola på Sofiehem som är planerad att stå klar 2017.

    Syftet med arbetet är att undersöka om det går att spara energi och kostnader genom att använda sig av en styrd ventilation istället för konstantflödesventilation som är planerad. Eftersom det är dyrare att investera i en styrd ventilation kommer det också undersöka återbetalningstiden för den investeringen.

    För att göra undersökningarna har programmet IDA ICE använts för att rita upp en modell av byggnaden och simulera dess energianvändning för att senare jämföra resultaten och se skillnaderna mellan de olika ventilationssystemen. Ett förslag har framtagits på hur ventilationskanalerna kan dras om för att få plats med en installation av VAV-spjäll med tillhörande ljuddämpare.

    Resultatet från simuleringarna gav att den totala energianvändningen sjönk med 18 % med styrd ventilation och det minskade den totala energiförbrukningen med 22 000 kWh/år. Av den minskningen stod fläktens energianvändning för 46 % och uppvärmningen via fjärrvärme för 54 %.

    Investeringen för styrd ventilation jämfört med konstantflödes ventilation är 168 000 kr mer och får utifrån beräkningarna i detta arbete en återbetalningstid på 12 år. Livslängden på ventilationssystemet antas vara 25-30 år.

  • 234.
    Inga, Mikael
    Umeå University, Faculty of Science and Technology, Space Science.
    REXUS II: rocket borne experiments for university students2005In: 17th ESA symposium on European rocket and balloon programmes and related research, Paris: European Space Agency, 2005, Vol. 590, p. 81-85Conference paper (Other academic)
    Abstract [en]

    This paper is about the student part of REXUS II. Students at the Department of Space Science were invited to join a EUROLAUNCH rocket campaign. This was done with a short time of notice but we accepted the offer and have tried to do our best despite the lack of time. The attendees are spread over several programs at the Umea University, Lulea University of Technology and Upper Secondary Space School, Kiruna which has lead to some interesting and challenging problems for the project managers. The launch of the rocket, an improved Orion rocket, was a success. It was launched from SSC, Esrange at 21:53 local time the 28(th) of October 2004. All of the experiments didn't deliver the expected data or didn't even work but still the members of the experiment teams did learn a lot. So, despite the faults it was still a success if the participators someday use the gained knowledge and experience.

  • 235.
    Iraeus, Johan
    et al.
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery. ÅF Industry, Gothenburg, Sweden.
    Lindquist, Mats
    Umeå University, Faculty of Medicine, Department of Surgical and Perioperative Sciences, Surgery.
    Pulse shape analysis and data reduction of real life crashes with modern passenger cars2015In: International Journal of Crashworthiness, ISSN 1358-8265, E-ISSN 1754-2111, Vol. 20, no 6, p. 535-546Article in journal (Refereed)
    Abstract [en]

    The increased use of computer simulations such as finite element modelling for evaluating passive safety applications has made it possible to simplify and parameterize complex physical processes. Crash pulses derived from laboratory tests have been used in many studies to evaluate and optimize passive safety systems such as airbags and seat belts. However, a laboratory crash pulse will only be representative of the acceleration time history of a specific car crashing into a barrier at a specified velocity. To be able to optimize passive safety systems for the wide variety of scenarios experienced during real-life crashes, there is a need to study and characterize this variation. In this study, crash pulses from real-life crashes as recorded by event data recorders were parameterized, and the influence of vehicle and crash variables was analysed. The pulse parameterization was carried out using eigenvalue analysis and the influence that vehicle and crash variables had on the pulse shape was determined with multiple linear regression. It was shown that the change in velocity, the subject vehicle mass, and the properties of the collision partner were the variables that had the greatest effect on the shape of the crash pulse. The results of this study can be used to create artificial real-life pulses with different crash parameters. This in turn can be used for stochastic computer simulation studies with the intention of optimizing passive safety systems that are robust to the wide variation in real-life crashes.

  • 236.
    Isaksson, Emil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Bortförsel av kapspånor: Framtagandet av ett lösningsförslag till ViaCon Production AB2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport beskriver ett examensarbete som är sista delen i studierna på högskoleingenjörsprogrammet i maskinteknik vid Umeå Universitet. Projektets uppdragsgivare var ViaCon Production AB. Projektet genomfördes helt på ViaCon Productions fabrik i Lycksele.

    På fabriken i Lycksele tillverkas bland annat spiralformade korrugerade vägtrummor i plåt.Vägtrummorna tillverkas i en kontinuerlig längd som sedan kapas, när önskad längd uppnåtts.

    Under kapningen slungas vatten blandat med kapspånor in i trumman. Kapspånorna, som ligger kvar, rostar efter en tid och försämrar därmed intrycket av kvaliteten på produkten. ViaCon önskar därför att kapspånorna avlägsnas från trummorna innan dessa lämnar fabriken.

    Projektets mål var att hitta en lösning för detta, men också att ta fram ett konstruktionsförslag för implementering i dagens produktion.

    För att lyckas med detta utfördes en studie av produktionen samt produktionsdokument på företaget. Ett lösningsförslag valdes,  innefattande vatten och antaganden gällande trummans spiralformade korrugering. Därefter gjordes ett test för att undersöka lösningsförslagets funktion.

    Utifrån studien och det valda lösningsförslaget arbetades sedan ett konstruktionsförslag fram. Konstruktionsförslaget innebär att vatten spolas in i trumman samtidigt som denna roteras på en bänk med drivrullar. Skruveffekten på grund av spiralformen gör att vattnet kan skölja med spånorna ut ur trumman.

  • 237.
    Jakobsson, Alina
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Solvärme till Östersunds Rehabcentrums terapibad: Förstudie av förutsättningar för, - och lönsamhet med, solfångare för att värma terapibadet2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report treats whether it is viable to invest in solar heating to heat the therapy pool at Östersunds Rehabcentrum. The rehab center is owned by the county council of Jämtland and is located on Solliden in Östersund city. The solar heating where supposed to be a complement to the district heating that was heating the pool in the current situation. Later, it however showed that this was not the case. The pool is currently being heated by a radiator circuit that is being heated by the district heating. The temperature in this circuit is however controlled by the outside temperature. If the outside temperature is increased sufficiently, there is no need to heat the building with the radiators. What happens then is that the temperature in the circuit might fall so it no longer can heat the pool. When this happens, an electric heater of 15 kW kicks in to heat the pool instead. Studies of the control signal to this electrical heater show that it heats the pool approximately from the middle of April until the beginning of October. Calculations show that the electrical heating stands for 72 % of the annual cost to heat the pool, even though it heats the pool during half of its running time.

    Because of this, three options for investment where calculated based on the wishes of the client. One option is to connect the pool directly to the heat source, which is district heating, to eliminate the electric heating. The second option is to install solar heating after the pool has been connected directly to the heat source. The third option is to keep the current connection of the pool and only install solar heating. The last option is investigated to compare the viability in solar heating depending on current heat source. The solar heating systems have been dimensioned to cover the pools energy demand during optimum conditions, with a working temperature in the solar collectors of 50°C. This is to avoid problems with not having use of the energy from the solar collectors during optimum conditions. Four different solar collectors are compared, two flat plated and two collectors with vacuum pipes.

    To determine the viability of the investments their pay-back time and present value have been calculated. The life-span of the solar collectors is approximated to 40 years and the cost of capital is 4 %. The annual increase in energy cost for electricity and district heating is calculated to 4 and 3 %, respectively. There is a possibility to receive financial support for some investments, this has however not been taken into account in the calculations.

    The results show that the most viable investment is to connect the pool directly to the district heating. The pay-back time is only one year and the annual cost for heating the pool becomes less than half of what it is today. The profit after 40 years becomes 1,6 million kr. Investing in solar heating that replaces the district heating proves not viable during the 40 years period. If the connection to the radiator circuit is retained, all of the solar collectors become viable. Most viable in this case is the solar collector 24-ST, with a pay-back time of 16 years and a profit of 1,3 million kr during the calculation time.

  • 238.
    Jakobsson, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energibesparing i industrilokal: En IDA ICE studie2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Reducing the energy consumption in older buildings is growing to be more important by each passing day as the cost of energy rises and political strides are made to limit the amount of energy used for various purposes. To optimize the use of energy in a building can be described as getting the same end result with a lower amount of spent energy, for the user this is an economic victory as he doesn’t have to spend as much money on heating his building while society gains a reduced impact on the environment and climate. In this thesis that you hold in your hands I have investigated an industrial building located in Teg, Umeå where I utilized the simulation software IDA ICE to simulate the buildings energy usage and the effects of various energy optimization/saving measures if implemented. The measures simulated are: Additional insulation for walls and roof, the switch to a ventilation system with a heat recovery unit, switching to well insulated windows, and switching the doors and garage doors to well insulated units.

    The work has mostly been done through studies of literature and IDA ICE where a model of the building has been constructed according to the specifications of the real world counterpart. The results from the various simulations are then compared with each other and the reference case.

    The results showed that all energy saving measures would result in a lowered use of energy. The biggest saving was gained from the changing out the ventilation system which resulted in a 49,3 % reduction whilst changing windows only resulted in a 0,7 % reduction.

  • 239.
    Jakobsson, Hanna
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Momentbroms för bandtransportör: Matematisk modellering och validering av moment för bandtransportörer inom gruvindustrin2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport har utförts som ett examensarbete i Maskinteknik vid Umeå universitet på sektionen Styrsystem Service ABB AB i Umeå i samarbete med anrikningsverket G1A på New Boliden AB. 

     

    Det huvudsakliga syftet med rapporten är att undersöka möjligheten och om möjligt utforma en momentbroms för bandtransportörer inom gruvindustrin. Tanken är att momentbromsen ska stanna bandet om motorns moment överstiger det förväntade värdet utifrån hur mycket malm bandet är belastat med. Ett motormoment som överstiger det förväntade värdet skulle kunna tyda på att t.ex malm fastnat i transportören. Momentbromsen skulle då kunna aktiveras och stoppa bandet. Detta skulle medföra mindre skador på bandtransportören och förkorta tiden och kostnaden för driftstoppen.

     

    Till grund för att utforma en momentbroms ligger motormomentet och motorns varvtal som avläses kontinuerligt via den drivande asynkronmotorns frekvensomvandlare. Dessutom används ett spårningssystem som talar om var malmen befinner sig på transportören samt malmens massa.

     

    En specifik bandtransportör på G1A i Boliden valdes ut för examensarbetet. Från denna bandtransportör loggades samplingar om motorns moment, effektförbrukning och varvtal. Även malmmassan som transporterades på bandtransportören loggades. På den utvalda bandtransportören utfördes momentberäkningar samt ett flertal tester under projektets gång.

     

    Resultatet blev två funktionsblock i styrprogrammet Control Builder avsedda för att efterlikna det förväntade motormomentet. Det ena funktionsblocket bygger på ren trendanalys och det andra på momentberäkningar som grundar sig på hur bandtransportören är designad med lyftvinklar, transportrullar m.m. Gemensamt för de båda metoderna är att de endast går att tillämpa då motorn kommit upp i nominellt varvtal.

     

    Då motorn kommit upp i 100 % av nominellt varvtal håller sig det beräknade motormomentet inom intervallet +5 till -6 procentenheter av nominellt motormoments avvikelse från det verkliga motormomentet. Motormomentet framtaget med trendanalys håller sig inom intervallet +6 till -7 procentenheter av nominellt motormoments avvikelse från det verkliga motormomentet.

     

    För att kunna använda sig av en momentbroms vid alla varvtal behöver metoden för att beräkna det förväntade motormomentet vid acceleration och inbromsning utvecklas.

  • 240.
    Janse, Joakim
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konceptdesign av låsmekanism till frontlastare2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Följande rapport behandlar en konceptutveckling av en låsmekanism vars syfte är att låsa fast en frontlastare mot en traktor. Arbetet är utfört på Ålös produktutvecklingsavdelning i Brännland. Bakgrunden till arbetet är att Ålö har ett intresse i att uppdatera dagens lösning på låsmekanismen med en ny design och ta fram en lösning som är mer kompakt och mer hållfast. Det nya konceptet skulle också vara bakåtkompatibelt så inga modifieringar fick göras på någon av detaljerna där låsmekanismen är infäst, det vill säga samma infästningshål som används idag skall även användas till konceptet.För att underlätta arbetet undersöktes dagens låsmekanism och eventuella problem som finns med denna. Det visade sig då att en stor del av dagens reklamationer beror på felaktig montering av låsmekanismen.Tre olika koncept togs fram. Av dessa valdes det mest realistiska alternativet ut för vidare arbete. Materialval gjordes på varje ingående komponent med avseende på bland annat pris och bearbetningsmetod. Konceptet jämfördes sedan storleksmässigt mot dagens mekanism med hjälp av CAD-programvaran. I denna jämförelse visade det sig att konceptet har en lägre bygghöjd jämfört med dagens lösning. Tre teoretiska lastfall beräknades och utifrån dessa utfördes en finita elementanalys av både dagens mekanism och konceptet i CAD programmet. I denna analys blev det bekräftat att konceptet kan bära högre laster. En fysisk modell i plast togs fram med en 3D skrivare och denna användes för att utvärdera mekanismens ergonomi och för att få en bättre bild av designen. Efter en utvärdering av konceptet utfördes mindre ändringar i konstruktionen.En monteringsinstruktion till mekanismen togs fram. Tanken med denna monteringsanvisning var att minska risken för felaktig montering, detta för att undvika framtida reklamationer.

  • 241.
    Jansson, Erik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av testrigg: Testrigg för provning av brunnslock2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report describes the design process of a test rig to be used for testing of manhole covers. The project owner is Brunnspecialisten Sverige AB, which sells proprietary manhole covers made of glass-fiber reinforced plastic. These manhole covers must meet the European standard, and therefor withstand excessive load testing.The purpose of the work, and the construction of the test rig, is that the previous standard has been revised and hence the tests become more advanced and an automated system will be required in high-cycle fatigue tests.The work has been based on the standard that defines testing of manhole covers. This led to a concept study where various design concepts were developed and evaluated. Calculations were made to dimension the components of the test rig in order to ensure strength. Then construction were dimensioned based on 3D models.The structure is dimensioned to test manhole covers up to class D400, which means it must be able to be withstand 400kN + 100kN.The results are drawings for manufacturing and calculations regarding calculation to ensure that the test rig can withstand the forces and stresses that occur when a manhole cover is tested according to a certification class.This report covers only the mechanical design of the test rig. But it will be equipped with a hydraulic system that applies the force and an associated control system in order to perform the tests.

  • 242.
    Jansson, Victor
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av skivstänger: Ett tillverkningsunderlag för sex olika typer av skivstänger2017Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [en]

    Lars Norberg with his company Balticfitness wants to compete with the largest companies on the market for barbells, wanting to make the best ones. By starting to manufacture their own bars and sell in their store. The project is about finding six different types of barbells that Lars wants to produce; IWF mens and women’s, Crossfit mens and women’s, IPF and a technical bar. The goal is to produce a manufacturing basis for all of the bars. The project is divided on two people, me and Filip Holmberg. I took responsibility for the choice of materials, knurls and surface treatment, while Filip took responsibility for the bearing solution and the sleeves.

     

    To select materials for the bars that met the requirements, many companies were contacted to hear what they recommended. By using the information from the companies that were contacted, it was concluded that one of these steels would be appropriate; SS 2541 (356Q) from Ovako, Uddeholm Deivar or Uddeholm Unimax. In the end, Ovako's SS 2541 (356Q) was chosen as it would need the least manufacturing steps, yet good enough strength. To find out if the material would handle the stresses it will be exposed to, FEM analysis was used in the program Solidworks.

     

    The choice of knurl is different for each bar but all bars have cross-sectional pattern. The grip for each bar; IWF bars were chosen to be medium, the Crossfit and technic bars to mild and IPF bar to rough.

     

    The surface treatment was selected for chrome plating for all bars except for the IPF and technic bars. These bars did not get any surface treatment at all.

     

    In the end the project was successful and most of the requirements were met. The only requirements that were not achieved were the strength of the women’s barbells. In practice, however, the bars will handle sufficient loads without any problems.

  • 243.
    Johannesson, Daniel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    CO2 and Cost Impact of Pre-and Post shift of Residential Electric Loads2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Royal Seaport project, which is a project in the Clinton Climate Initiative, develops a new, sustainable city area in Stockholm and aims to reduce the greenhouse gas emissions, using pre- and post load shifting methods to reduce the peak electricity load. The Active House, that is one work package in the Royal Seaport project, is a residential building that is equipped with systems for automated demand response, such as smart appliances and electricity storage, and also local photovoltaic power and charging poles for electric vehicles.

    The thesis investigates if pre- and post shifting electricity load will reduce greenhouse gas emissions and electricity cost for the residents in the Active House. The greenhouse gas emissions are investigated for three Clinton Climate Initiative cities, Stockholm, London and San Francisco to further calculate the pre- and post shifting impacts of greenhouse gas emissions and electricity cost.

    A simulation tool based on statistics of the power systems is developed, to investigate the greenhouse gas emissions from electricity production and the simulator is used to solve the research questions in the thesis. The simulator calculates an hourly greenhouse gas intensity distribution during the day and the results are used to observe differences between seasons and countries. The electricity loads of the households in the Active House are also investigated to determine the peak electricity loads to be able to dimension the photovoltaic power system and electricity storage.

    Some of the most important results and conclusions in the thesis are:

    The relationship between the greenhouse gas emissions and the electricity production determined, in most cases the greenhouse gas intensity distribution has a similar shape as the consumption and electricity price.

    The photovoltaic power system will be able to provide 30 % of the fixed building electricity load. The electricity storage could be charged during night, when the greenhouse gas intensity is low, or when the photovoltaic power system generates surplus electricity that otherwise would be given away to the utility grid.

    The dimensions of the electricity storage are cycled one time during the day and calculated to be 205 kWh to be able to pre shift an electricity load of 114 kWh from the electricity peak in the afternoon. The electricity storage are able to reduce the peak power with 40 kWh/h, electricity cost with up to 137 SEK and the greenhouse gas emissions with up to 13 kg CO2 depending on season and country.

    The electricity storage is not profitable in an economical point of view today, because of life time of the electricity storage and the electricity price today but mostly on the high investments cost. The cost of reducing the greenhouse gas intensity is between 8-55 SEK/ kg CO2 in average during a year, depending on season and country. The investment cost of electricity storage will be reduced in the future and in 3 years it could be profitable with electricity storage in some countries.

    Further investigations about the impact of greenhouse gas emissions and electricity cost for smart appliances and electrical vehicles have also been done in this thesis.

  • 244.
    Johansson, Andreas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energiutvinning i Fumingverket på Rönnskärsverken2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The project was conducted as a thesis in engineering education with a focus on energy. The work was done at New Boliden’s smelters, Rönnskärsverken, in Skellefteå.

    The purpose of this degree of project was to find a more economically optimal process in the fuming plant for zinc- and energy production and improve the interaction between the energy center. Largest producer of steam and district heating at Rönnskär smelter is the fuming plant.

    Different operation modes affect both production of steam and district heating. Availability of zinc rich slag and reduced steam production over tapping of slag has the biggest influence. At low production of steam at the fuming plant and a big need of steam at the rest of Rönnskärs processes together with big consumption of district heating an oil-fire boiler is used to maintain then need of steam. The consumption of oil is a significant cost at Rönnskär smelter.

    During the last years the energy production have decreased dependent of zinc- production. Preliminary calculations show that variations in the fuming plant operations leads to large variations in the steam production.

    A mass- and energy balance for cold crushed slag has been calculated to control how much energy that are cooled down by water before the precipitator. The result shows that 14 MW could be recovered.

    Attempt to lower the oil consumption independent of how the fuming are operated was calculated and experiments were performed. A short-term solution can be reached with the plastic burning and a longer-term with installation of an economizer.

    Pay-off for the economizer is reached by lowering the oil consumption. Data from March 2010 shows an approximate 30 % less oil consumption. A similar result in about nine month per year with an investment cost of 15 million, gives a pay-off in about four years. Additional oil can be saved with continuous plastic combustion which can give up to 60 % less oil consumption. The procedure can be established by investment in an charging bin.

    A short-term solution for steam production, that can be used today, is to mix plastics with the cold crushed slag in order to increase the energy production and lowering the coal consumption. This because of plastics contains coal and hydrogen which also can act as a reducing agent.

    Experiments to check if plastic combustion can be used during slag converting or under tapping of the zinc reduced slag were done. Reduced oil consumption under three batches estimates that about 14 tkr can be saved. Experiment under tapping shows that there are opportunities to stabilize the steam flow which gives fewer start and stop combustions in the oil-fire boiler.

  • 245.
    Johansson, Andreas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konsekvenser av ett omfattande elavbrott inom den kommunala äldrevården2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During the last couple of decades the society has gone through a change where advancement in technology development have meant a transformations from at industrial society to an information society. In today’s society, almost everything contains components which depends on electricity to function. An increasing dependence on electricity makes the society vulnerable and especially the healthcare chain. The Swedish hospitals have capacity to handle longer power breaks, but a subsector which have not been investigated in the same extent is the municipal retirement homes.

     

    This thesis will look into the municipal retirement homes situation during a long and large-scale power outage with critical weather conditions. The thesis will analyze the consequences that might emerge due to a power outage and to what extent there is capacity to manage a situation like this which often mean some sort of emergency power.

     

    The work consisted of calculating the power requirement for a reference building during critical weather conditions. Furthermore, a simulation was done to investigate the time it took for the building to cool down during a cold winter period with the absent of a heating system and also what the indoor temperature would be in the building during a warm summer period with no access to a cooling system. The work was done with the simulation program IDA Indoor Climate and Energy and hand calculations. In addition, the consequences of a power break for retirement homes was analyzed, what capacity there is to handle this and measures that can be implemented.

     

    The result of the work shows that the dependence of electricity is rather large and the consequences of a large-scale power outage can result in big impact on the retirement homes. Important functions in the society might be affected which will make the situation in the retirement homes even worse. The temperature inside the building decreases rapidly without heating systems during a cooled winter period and a hot summer period without a cooling system would mean great stresses on the retirement homes. The ability to manage a large power break varies in the municipality and in some parts there is no resources in the form of emergency power. The result also shows that it requires quite big emergency power generators to meet the power requirement. These generators consume large amount of fuel and it is therefore important to have a well-functioning fuel supply plan.   

  • 246.
    Johansson, André
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivisering av ett uppvärmningssystem vid två sameskolor i Karesuando, Norrbotten2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Specialfastigheter Sweden AB manages two properties in Karesuando, Norrbotten. The properties are used as Sami schools with children from kindergarten to sixth grade. The properties have a heating system that consists of two oil-fired boilers and a number of water heaters that supplies heat in the form of a warm water heating system. These boilers are located in separated buildings, in event of a stop on one single oil-fired boiler, can in the worst scenario only one oil-fired boiler supply both buildings. This is neither sustainable nor an energy -efficient solution.

    An energy- efficient solution to this problem is required to reduce its dependence on oil and the high cost of both transportation and purchasing. The best option that applies to these properties is to convert the current oil-fired boilers to a geothermal heating system when a connection to the district heating or solid fuel boiler is not an option. The purpose of this work is to find alternative energy efficient solutions for replacement of a fossil fuel heating system and reduce the heating costs for two Sami Scholes in Karesuando, Norrbotten.

    By calculating the properties total thermal energy losses in the form of heat, using different heat resistance, thermal transmittance and transmission losses, resulted to a energy loss of 217 500 kWh/year. With this information, the dimensioning of the geothermal heating system six main parts could begin. These parts are dimensioning of the drill hole, heat pump, additional heating, water heater, heat emission system or so called radiators, and at last the electric service line.

    The geothermal heating system is calculated to cover 60-70 % of the property's maximum heat demand, which result to cover approximately 90% of the property’s annual heat demand. The remaining 30-40 % is additional heating.

     An renewed heating system with a geothermal heat pump size of 72 kW and additional heating  at 27 kW, giving an annual reduction of heat costs at 162 000 SEK and an annual profit of 111 000 SEK in comparison with the oil-fired boilers heating system.

  • 247.
    Johansson, Anna
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energieffektivisering av ventilationssystem: Boliden Aitik2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Aitik is a Coppermine located in Gällivare, a small community in northern Sweden where the winter season can be very cold, which means that much energy is required for heating. In order to keep the mining industry as energy efficient as possible, continuous improvements are made to the different processes. Ventilation is not the biggest item when it comes to energy efficiency, but there is still potential to save both economically and energy-efficiently.

    In Aitik there are pump stations to pump up water from the mine, these stations are located in the mountain. To get good conditions in the pump station it requires ventilation and some heating. In pump station 420 it is large volumes to be ventilated, which means large amounts of outdoor air to be heated. Heating batteries does the heating of the outdoor air, these batteries are powered by electricity. The ventilation has the function of removing heat from pumping stations and plants located in the pump station, but also removing diesel gases and radon. The exhaust air is forced through a port that is slightly open all year long. Pump station ventilation is in need of energy efficiency, it is also possible to read from previous documentation that it is in need of improvement. To find potential energy efficiency measures, an analysis of the current ventilation is made using the ABB control system 800xA and documentation about the pump station and some minor measurements of radon and exhaust air temperature. The analysis is then compared with the action proposals that include replacing current ventilation into an FTX aggregate and also a minor action proposal that involves temperature reduction. The comparison takes place both from an energy point of view and from an economic point of view. The result shows that a total energy savings of approximately 64 % can be achieved with an FTX aggregate, where the heat exchanger produces an energy saving of 68 % compered to air heating batteries. The economic part of this result demonstrates that this investment is profitable and has a short payback time. Lowering the temperature would generate an energy saving of about 16 % and the relative humidity would increase slightly but still be within acceptable range. The economic result of this measure gives a smaller amount of cost savings. 

    The full text will be freely available from 2019-10-09 21:50
  • 248.
    Johansson, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lyftverktyg till Crispo Rocker: Monteringsfixtur V16866 för montering och förflyttning av Crispo Rocker2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    GE Healthcare in Umeå manufactures equipment for hospitals and the pharmaceutical industry. In order to stay competitive they are constantly developing new and improved products. To fulfill internal and external health and safety regulations they must frequently develop lifting tools to transport products in the productions line.The newly developed product Crispo Rocker needs a new lifting device that can lift up and move the instrumentet from the assembly line to a testbench for the final testing. Since the instrumentet have some parts that must be attached to the underside of it, therefore the liftingdevice needs to be able to rotate the instrumentet during the lift in such a way that the final fitting can be done in a simple way.To complete the mision, several designconcepts have been developed and presented. From them, a liftingtool has been constructed that meets all requirements. For a tool to be put into use in the assembly area at GE, the equipment has to be CE-marked. Therfore a CE-survey has been conducted and several documens required to CE-mark a liftingtool has been produced.

  • 249.
    Johansson, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utredning av köldbärarsystem med avseende på effektivitet och kapacitet2017Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [sv]

    Massa- och pappersindustrin utgör en stor andel av energianvändningen i den svenska industriella sektorn. Den energiintensiva industrin innebär en stor möjlighet till besparingar genom energieffektiviserande åtgärder. Denna rapport utreder ett köldbärarsystem som förser eltekniska driftrum med kyla samt avfuktar luften på pappersbruket Smurfit Kappa Piteå. På pappersbruket upplever man i dagsläget att deras köldbärarsystem fungerar ineffektivt och får som följd inte ut den projekterade kyleffekten. Syftet med denna utredning är att öka effektiviteten och kapaciteten på köldbärarsystemet. Målet var att ta fram åtgärdsförslag som bidrar till att uppfylla utredningens syfte. Genomförandet av utredningen har behandlats i tre del- system: Distribution av kyla, produktion av kyla samt användning av kyla. Det huvudsakliga tillvägagångssättet har varit analys av loggade data från styr- regler- och övervakningssystemet Larmia. Utöver detta har också driftprov utförts på kylmaskinerna.

    I undersökningen av distributionssystemet visade det sig att återströmning erhålls i köldbä- rarsystemet, vilket gör att redan kyld köldbärare leds in i kylmaskinen KC2. Detta leder till minskad effektivitet. Problemet med återströmning kan minimeras genom att komplettera det befintliga styrsystemet med en stoppsignal som stänger kylmaskiner vid ett lågt kylbehov.

    Undersökningen av kylmaskinerna visade att KC3 och KC4 fungerar suboptimalt. Vid drift av KC3 varierar utgående köldbärartemperatur kraftigt, vilket medför att den löser ut på frysskydd vid låga börvärden. På grund av detta är börvärdet i dagsläget ställt högre än vad som är önskvärt. För att kunna sänka börvärdet och därmed öka KC3’s kapacitet föreslås en flödesökning, så variationerna dämpas genom värmeväxling till en större värmekapacitet. Denna åtgärd kräver att KC3’s cirkulationspump byts. Driftprovet på KC4 visade att expan- sionsventilen i en av köldmediekretsarna hela tiden är fullt öppen. Detta är en indikation på att ett otillräckligt flöde erhålls i förångaren, då expansionsventilens uppgift är att reglera flödet för att hålla konstant överhettning. Det otillräckliga flödet är orsakat av ett för lågt kondensortryck. Detta leder till att förångaren inte nyttjas fullt. Orsaken till detta är en dålig vattensparventil, som reglerar kylmedelflödet till kondensorn. Lösningen på detta är att byta ut ventilen mot en reglerventil, som styrs mot önskat börvärde på kondensortrycket. Utöver detta bubblar det i synglaset i köldmediekrets 2 och rörtemperaturen ut från economisern och kondensorn är höga, vilket tyder på att något är fel. Detta kan bero på bland annat låg köldmediefyllnad, fel på economisern eller på kondensorn. Som åtgärd på detta föreslås att kylmaskinleverantören kontaktas för felsökning.

    Undersökningen av kylanvändarna visade att totalt 39 styrventiler var fullt öppna under he- la sommaren 2016, där 20 av dem styr avfuktningen i eltekniska driftrum. Orsaken till fullt öppna styrventiler till avfuktarna är att det inställda börvärdena på temperatur och relativ fuktighet är för låga. Detta gör att tillräcklig avfuktning är omöjlig vid rådande köldbärartem- peratur. Problemet kan lösas genom att höja börvärdena eller sänka köldbärartemperaturen. Resterande 19 styrventiler är till luftkylare. Anledningen till de fullt öppna styrventilerna kan bero på att köldbärarflödet är för lågt, luftflödet är för lågt eller att mer elektrisk utrustning installerats i driftrummen. Som en första åtgärd föreslås en justering av köldbärarflödet med injusteringsventilerna för att se till att rätt flöde erhålls i köldbärarsystemet.

  • 250.
    Johansson, Daniel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Slutväxel HFT: Konstruktionskoncept för banddriven skotare2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sveriges samlade skogsindustriföretag förutspår en förlust av marknadsandelar, eftersom man inte lyckas hålla samma tempo på produktionen som många andra länder. En orsak till detta är att skogsmaskinerna är för långsamma. Skotarna, vars uppgift är att förflytta virket från avverkningsplatsen till en uppsamlingsplats, bär en stor del av skulden. De hinner inte transportera virket tillräckligt snabbt. För att råda bot på detta ska en ny typ av skotare utvecklas, vars plattform inspireras av försvarsteknologi. Tack vare sin långa erfarenhet av banddrivna fordon har BAE Systems Hägglunds i Örnsköldsvik fått i uppdrag att konstruera en prototyp, som baseras på deras framgångsrika bandvagn, BvS10.[A]

     

    Skotaren går under namnet Hybrid Forestry Truck (HFT), och är en banddriven skotare med fyra larvband. Framdrivningen är av seriehybridtyp, vilket betyder att en generator drivs av en dieselmotor. Dieselmotorn förser sedan fyra elmotorer, en i varje bandställ, med ström.

     

    Detta examensarbete går ut på att utveckla länken mellan elmotorn och drivhjulen till banden. Tre designkoncept presenteras och analyseras. Den, i författarens åsikt, mest ideala lösningen utvecklas sedan vidare mer detaljerat.

    Många andra examensjobb, samt interna analyser av Hägglunds själva, har gjorts på HFT. Detta innebär att många kraftsituationer och belastningsfall redan är uträknade, samt att de flesta komponenterna till slutväxeln är utvalda.

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