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  • 251.
    Brembilla, Christian
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Efficiency factors for space heating system in buildings2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The thesis focuses on the efficiency of the space heating system. In particular, the efficiency factors measure the efficiency of thermal zone. The efficiency factors measures how the energy is used in a space heating. Efficiency factors relatively close to one mean that the energy is used "efficiently'', by contrast, efficiency factors close to the zero mean that the majority of the energy is lost to the outdoor environment. This method for the appraisal of space heating performance reads as if it is apparently simple and intuitive. In reality, the efficiency factor method has several pitfalls.

    The thesis provides tools, insights and remarks on how to apply the efficiency factor method to space heating systems equipped with hydronic panel radiator and floor heating respectively. Models of the latter heaters together with the multilayer wall were developed and validated to understand the reliability of their predictions. The hypothesis is that the heat stored in the building thermal mass and heaters plays a role in defining the building thermal performance and as a result in the appraisal of the efficiency factors. The validation is based on the sensitivity bands of the models' predictions. The heaters were tested in in a thermostatic booth simulator. Benefits and drawbacks of each model were highlighted to increase awareness of their use in the engineering fields. The results showed how the models accounting for the heat stored performed the charging phase. In addition, results of how the multilayer wall delayed and damped down the heat wave coming from the outdoor environment were presented with the appraisal of the decrement factor and time delay of the indoor temperature. The results of the efficiency factors analysis reveal how the weather affects the efficiency of each locality situated in cold climates. Lastly how different control strategies impact on the efficiency factors of space heating and its distribution system. To conclude, this study highlights the paradoxes around the efficiency factor method. The thesis proposes how such factors have to be interpreted by researchers and scientists tackling the lack of information around this topic.

  • 252.
    Brembilla, Christian
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Modelling and simulation of building components: thermal interaction between multilayer wall and hydronic radiator2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background and Scope The scope of this thesis is to investigate the thermal behaviour of building components as hydronic radiator and multilayer walls subjected to dynamic conditions. The modelling and simulation of these building components provide information on how these components thermally interact among each other. The thermal interaction is fundamental to know how the energy is used in buildings. In particular, the thermal energy used in rooms can be expressed as the efficiencies for emission in a space heating system. This thesis analyzes the efficiencies for emission of a space heating system equipped with hydronic radiator for Swedish buildings by providing a comprehensive and detailed approach on this topic.

     

    Methodology The methods used in this thesis are: experiment, modelling of multilayer wall and hydronic radiator, the dynamic simulation of the building and the efficiencies for emission of a space heating system. Here, the experiment, known as step response test, shows the heating up process of a hydronic radiator. The observation of the qualitative measurements suggests the most suitable technique of modelling the radiator known as transient modelling with multiple storage elements. The multilayer wall has been discretized both in space and time variable with a Finite Difference Method. Dynamic simulation of the building provides the efficiencies for emission of a space heating system.

     

    Findings The experimental results show how the radiator performs the charging phase. The performance of the transient model is compared with lumped steady state models in terms of temperature of exhaust flow and total heat emitted. Results of the dynamic simulation show how buildings located in a Northern climate use the energy in a better way than Southern climates in Sweden. Heavy active thermal mass provides higher efficiencies for emission than light thermal mass. Radiators with connection pipes located on the same side react faster at the thermodynamic changing of the mass flow rate by providing higher efficiencies for emission than radiators with connection pipes located on the opposite side.

     

    Conclusion and Outlook This thesis increases the knowledge about the modelling and simulation of hydronic radiators and multilayer walls. More research is needed on this topic to encompass modelling details of building components often ignored. The modelling and simulation of building components are the key to understand how building components thermally interact with each other. The thermal interaction among building components is a fundamental parameter for the assessment of efficiencies of emission of the space heating system. In the near future, the concept of efficiencies of emission can be implemented in National Building Code, therefore, this study provides guidelines on how to assess these efficiencies.

  • 253.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lacoursiere, Claude
    Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Soleimani-Mohseni, Mohsen
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Investigation of thermal parameters addressed to a building simulation model2015In: Energy, Science and Technology 2015: Book of Abstracts. The energy conference for scientists and researchers / [ed] Karlsruher Institute of Technology (KIT), Karlsruher, Germany: Karlsruher Institute of Technology (KIT) , 2015, Vol. 1, p. 128-Conference paper (Refereed)
    Abstract [en]

    Introduction The uncertainty of setting input parameters in a building model can have a major impact on the simulated output. The tolerance of thermal parameters is a necessary information that helps modeler to know the influence of eachfactors on the outcomes. This paper shows the allowable tolerance of thermal parameters in order to build anaccurate building model.

  • 254.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lacoursiere, Claude
    Umeå University, Faculty of Science and Technology, High Performance Computing Center North (HPC2N).
    Soleimani-Mohseni, Mohsen
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Investigations of thermal parameters addressed to a building simulation model2015In: Proceedings of BS2015, India, Hyderabad: International Building Performance Simulation Association (IBPSA), 2015, , p. 2741-2748p. 2741-2748Conference paper (Refereed)
    Abstract [en]

    This paper shows the tolerance of thermal parameters addressed to a building simulation model in relation to the local control of the HVAC system. This work is suitable for a modeler that has to set up a building simulation model. The modeler has to know which parameter needs to be considered carefully and vice-versa which does not need deep investigations. Local differential sensitivity analysis of thermal parameters generates the uncertainty bands for the indoor air. The latter operation is repeated with P, PI and PID local control of the heating system. In conclusion, the local control of a room has a deterministic impact on the tolerance of thermal parameters.

  • 255.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    One dimensional model of transient heat conduction through multilayer walls/slabs: The functionality of insulation and brick materials in terms of decrement factor and time lag2016Manuscript (preprint) (Other academic)
    Abstract [en]

    Multilayer wall is a common type of building envelope used in buildings located in cold climates. The building envelope is typically composed by internal and external masses made by bricks or concrete separated by a large thickness of insulation material. This paper investigates the thermal behavior of a multilayer wall subjected to temperature excitation on both wall sides. The analysis is conducted by discretizing the continuous space and time variables of the mathematical model identified in the heat equation. Euler backwards solves the numerical model of multilayer wall by providing an unconditionally stable solution. The step response test shows the correct working of the model which reaches the steady state solution. The results of this paper are expressed in terms of temperature of each wall layer against the time. In particular, (i) the large thickness of insulation material separates thermodynamically the outside external mass from the internal mass, (ii) 20 cm thickness of insulation material damps the heat wave with a decrement factor of 3.41 °ͦC and a time lag of 1 hour, (iii) the external brick layer damps the heat wave with a decrement factor of 1.97 °ͦC and a time lag of 5 hours.

  • 256.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Renman, Ronny
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Soleimani-Mohseni, Mohsen
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    The impact of control strategies on space heating system efficiency in low-energy buildings2018Manuscript (preprint) (Other academic)
    Abstract [en]

    In this study efficiency factors measures the thermal energy performance for space heating. This study deals with the influence of control strategies on the effriciency factors of space heating and its distribution system. An adaptive control is developed and applied to two types of heating curves (linear and non-linear) for a low-energy building equipped with renewable energy sources. The building is modelled with a hybrid approach (law driven + data driven model). The design of the floor heating is calibrated and validated by assessing the uncertainty bands for low temperatures and mass flow rate. advantages and disavantages of linear and non-linear heating curves are highlighted to illustrate their impact on space heating thermodynamic behaviour and on the efficiency factors of the space heating system.

    Practical application: The study reveals that applying commercial building energy simulation software  is worthwhile to determine reliable performance predictions. Oversimplified building models, in particular when considering building thermal mass, are not capable of simulating the thermodynamic response of a building subjected to different control strategies. The application of different heating cuirves (linear and non-linear) to massless building models leaves the amount of mass flow rate delivered to the space heating unchanged when the building is subjected to sharp variations of the outdoor temperature.

  • 257.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Soleimani-Mohseni, Mohsen
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Hybrid heating system for open-space office/laboratory2015In: Energy, Science and Technology 2015: Book of Abstracts. The energy conference for scientists and researchers / [ed] Karlsruher Institut für Technologie (KIT), Karlsruher, Germany: Karlsruhe, KIT , 2015, Vol. 1, p. 315-315Conference paper (Refereed)
    Abstract [en]

    Open-space office/laboratory are quite common in Scandinavia and they are usually designed for multipurposework. There are office area where is possible to work standing up and in the same time to work at the desk. Forthis purpose a hybrid heating system made by electric convectors and panel radiators is investigated. Two stepresponse tests of the hybrid heating system are performed at the laboratory of Umeå University. The first test isexecuted during the week, disturbances from heat sources degrading the quality of the results. The second test isperformed during week-end. The error analysis shows a maximum discrepancies of +0.6 °C between measuredand simulated data. However, a thermal time constant of the room can be deducted and use it for controlling purposes.

  • 258.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Soleimani-Mohseni, Mohsen
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Transient model of a panel radiator2015In: Energy, Science and Technology 2015: Book of Abstracts. The energy conference for scientists and researchers / [ed] Karlsruher Institut für Technologie (KIT), Karlsruher, Germany: Karlsruher Institut für Technologie (KIT) , 2015, Vol. 1, p. 321-321Conference paper (Refereed)
    Abstract [en]

    This paper shows a detailed transient model of a panel radiator considered as a system of multiple storageelements. The experiment records the temperature surface of the panel in the process of heating up. Thequalitative results of the experiment suggest the more appropriate technique for modelling this technology. The transient model performs the modelling with horizontal thermal capacitances connected in series. This modelcalculates the temperature of exhaust flow, heat emission towards indoor environment, temperature gradient onpanel surface, dead and balancing time identified numerically on the chart.

  • 259.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Soleimani-Mohseni, Mohsen
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Transient model of a panel radiator2015In: Proceedings of BS2015: 14th Conference of International Building Performance Simulation Association, Hyderabad, India, Dec. 7-9, 2015, India, Hyderabad: International Building Performance Simulation Association (IBPSA), 2015, , p. 2749-2756p. 2749-2756Conference paper (Refereed)
    Abstract [en]

    This paper shows a transient model of a hydronic panel radiator modelled as a system of multiple storage elements. The experiment´s results suggest the more suitable technique for modelling this technology. The panel radiator is modelled numerically with eight thermal capacitance connected in series by keeping a memory of the heat injected in the thermal unit. The comparison of the performance among lumped steadystate models and transient model, in terms of heat emission and temperature of exhaust flow, shows the potential of the latter approach. To conclude, (1) the transient phase is essential for modelling stocky panels, and (2) this type of modelling has to be addressed for evaluating the performance of low energy buildings.

  • 260.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Vuolle, Mika
    EQUA simualtion.
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Practical support for evaluating efficiency factors of a space heating system in cold climates: modelling and simulation of hydronic panel radiator with different location of connection pipes2017In: Energy Efficiency, ISSN 1570-646X, E-ISSN 1570-6478, Vol. 10, no 5, p. 1253-1267Article in journal (Refereed)
    Abstract [en]

    Plenty of technical norms, included in the EPBD umbrella, assess the performance of buildings or its sub-systems in terms of efficiency. In particular, EN 15316 and its sub-sections, determine the system energy requirements and the system efficiencies of space heating system. This paper focuses on the estimation of efficiencies for emission of hydronic radiators. The assessment of efficiencies for emission occurs by evaluating the amount of heat emitted  from the heat emitter and the extra thermal losses towards building envelope. The heat emitted from radiators varies during the heating up/cooling down phases. A factor that influences the heat emitted during these phases is the location of connection pipes of the radiator. Connection pipes can be located on opposite side or at the same side of the radiator. To better estimate the heat emitted from radiators a transient model with multiple storage elements is used in a building simulation model. Sensitivity analysis encompasses all  the possible variations on extra thermal losses due to the building location in different climates, the heaviness of active thermal mass and the type of radiator local control. The final outcome of this paper is a practical support where the designer can easily assess the efficiencies for emission of hydronic radiators  for Swedish buildings. As main result, (i) the efficiency for control of space heating system is higher in Northern climates than in Southern climates, (ii) heavy active thermal masses allow higher efficiencies for emission than light active thermal masses, (iii) connection pipes located on the same side of the radiator enable higher efficiencies for emission than pipes located on opposite side.

  • 261.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Predictions' robustness of one-dimensional model of hydronic floor heating: novel validation methodology using a thermostatic booth simulator and uncertainty analysis2018In: Journal of Building Physics, ISSN 1744-2591, E-ISSN 1744-2583, Vol. 41, no 5, p. 418-444Article in journal (Refereed)
    Abstract [en]

    Hydronic floor heating models provide predictions in estimating heat transfer rates and floor surface temperature. Information on the model performance and range of validity of its results are often lacking in literature. Researchers have to know the accuracy and robustness of the model outcomes for performing energy and climate comfort calculations. This article proposes a novel validation methodology based on the uncertainty analysis of input data/parameters of one-dimensional model of hydronic floor heating tested in a thermostatic booth simulator and compared with experimental measurements. The main results are: (1) prediction accuracy between 0.4% and 2.9% for Tf and between 0.7% and 7.8% for qup when the serpentine has tube spacing (p) of 0.30 m, (2) prediction accuracy between 0.5% and 1.4% for Tf and between 8.7% and 12.9% for qup with p = 0.15m and (3) Tfld mostly affects predictions with oscillations between 6.2% and 2.2% for qup. This model provides robust and reliable predictions exclusively for qup when p = 0.30m.

  • 262.
    Brembilla, Christian
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Östin, Ronny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Soleimani-Mohseni, Mohsen
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Paradoxes in understanding the Efficiency Factors of Space Heating2018In: Energy Efficiency, ISSN 1570-646X, E-ISSN 1570-6478Article in journal (Refereed)
    Abstract [en]

    Efficiency factors are here defined as the thermal energy performance indicators of the space heating. Until recently, the efficiency factors were assumed as one value for space heating located inany climate. This study addresses the problem of how the outdoor climate affects the efficiency factors of a space heating equipped with 1D model of hydronic floor heating. The findings show how the efficiency factors, computed with two numerical methods, are correlated with the solar radiation. This study highlights the paradoxes in understanding the results of efficiency factors analysis. This work suggests how to interpret and use the efficiency factors as a benchmark performance indicator.

  • 263.
    Bretting, Viktor
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Bärverk i passivhus: Utformning och dimensionering av en limträ stomme till en passivhus skola2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 264.
    Brostrom, Markus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Pommer, Linda
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Branca, C.
    Di Blasi, C.
    Influence of torrefaction on the devolatilization and oxidation kinetics of wood2012In: Journal of Analytical and Applied Pyrolysis, ISSN 0165-2370, E-ISSN 1873-250X, Vol. 96, p. 100-109Article in journal (Refereed)
    Abstract [en]

    Devolatilization and oxidation kinetics of torrefied wood have been studied by evaluating thermogravimetric curves measured in nitrogen and air at various heating rates. Samples consist of Norway spruce wood chips torrefied at several process temperatures and residence times. Data about untreated wood have also been obtained for comparison. Measured curves are well predicted by means of a five-reaction mechanism, consisting of three devolatilization reactions for the pseudo-components hemicellulose. cellulose and lignin and, in air, of two additional reactions for char devolatilization and combustion. The torrefaction pre-treatment only requires model modifications in the amounts of volatiles generated from the decomposition of pseudo-components, indicating that only their relative percentages and not their reactivities are modified. On the other hand, a slightly different thermal stability is found for the char generated from torrefied wood, which results in higher activation energy and lower reaction order for the oxidation step. Hence torrefaction conditions can affect the subsequent conversion characteristics of the char product. (C) 2012 Elsevier B.V. All rights reserved.

  • 265.
    Broström, Marcus
    et al.
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Utveckling och utvärdering av mätteknik och additiv för alkalikomponenter i termiska energiomvandlingsprocesser2006Report (Other (popular science, discussion, etc.))
  • 266.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Aspects of alkali chloride chemistry on deposit formation and high temperature corrosion in biomass and waste fired boilers2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Combustion of biomass and waste has several environmental, economical and political advantages over the use of fossil fuels for the generation of heat and electricity. However, these fuels often have a significantly different composition and the combustion is therefore associated with additional operational problems. A high content of chlorine and alkali metals (potassium and sodium) often causes problems with deposit formation and high temperature corrosion. Some different aspects of these issues are addressed in this thesis.

    The overall objective of this thesis was to study and highlight different means by which operational problems related to alkali chlorides can be overcome, reduced or prevented.

    The most important results of this thesis are: (1) A full description of the in-situ alkali chloride monitor, its operational principles, the calibration procedure, and an example of a full-scale application was made public in a scientific publication. (2) Efficient sulfation of gaseous alkali chlorides in a full-scale boiler was achieved by injecting ammonium sulfate in a water solution into the hot flue gas. (3) Reduced deposit growth and corrosion rates were achieved by lowering the alkali chloride concentration in the flue gas by sulfation. (4) Evidence of decreased deposit growth and chlorine content in deposits during peat co-combustion. (5) Results are presented from high temperature corrosion tests with different superheater steels in two different combustion environments. (6) Controlled KCl and NaCl condensation under simulated combustion conditions resulted in deposits which consisted of mostly pure phases, in contrast to the solid solution that would be expected under the prevailing conditions at chemical equilibrium.

  • 267.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Effects of alkali chlorides in biomass and waste-fired boilers2009Licentiate thesis, comprehensive summary (Other academic)
  • 268.
    Broström, Markus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Andersson, Christer
    Axner, Ove
    Nordin, Anders
    IACM - In situ alkali chloride monitor2004In: 2nd World Conference for Energy, Industry and Climate Protection, Rome, Italy, 2004Conference paper (Other academic)
  • 269.
    Broström, Markus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Enestam, Sonja
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Mäkelä, Kari
    Condensation in the KCl–NaCl system2013In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 105, p. 142-148Article in journal (Refereed)
    Abstract [en]

    Condensation of gaseous KCl and NaCl is known to participate in deposit formation and high temperature corrosion processes in heat and power plants. Little is known about interaction between the two salts, which is of interest for the overall understanding of deposit and corrosion problems. Within this study, condensation at different material surface temperatures and salt mixtures was investigated.

    Salt vapors were prepared by temperature controlled evaporation. A cooled condensation probe with a temperature gradient was inserted in the hot gas. After exposure, the probe surface was visually inspected and analyzed with SEM/EDS and XRD for elemental and phase composition. TGA/DTA was used to provide complementary information on vaporization and sintering.

    The results indicated that a mixture of KCl and NaCl probably condenses as separate phases at concentrations and temperatures below the melting points of the salts. Condensation was possibly followed by a secondary sintering process. It was verified by TGA/DTA that a mixture of solid KCl and NaCl particles sinters and melts rapidly at temperatures above the melting temperature of a corresponding solution. It was also seen that sintering took place at lower temperatures with slow solid-gas interactions, possibly with the formation of solid solutions.

  • 270.
    Broström, Markus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Holmgren, Per
    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.
    Ash fractionation and slag formation during entrained flow biomass gasification2018Conference paper (Other academic)
  • 271.
    Broström, Markus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Kassman, Håkan
    Vattenfall Power Consultant AB, Box 1046, SE-611 29 Nyköping, Sweden.
    Helgesson, Anna
    Vattenfall Research and Development AB, SE-814 26 Älvkarleby, Sweden.
    Berg, Magnus
    Vattenfall Research and Development AB, SE-814 26 Älvkarleby, Sweden.
    Andersson, Christer
    Vattenfall Research and Development AB, SE-814 26 Älvkarleby, Sweden.
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Sulfation of corrosive alkali chlorides by ammonium sulfate in a biomass fired CFB boiler2007In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 88, no 11-12, p. 1171-1177Article in journal (Refereed)
    Abstract [en]

    Biomass and waste derived fuels contain relatively high amounts of alkali and chlorine, but contain very little sulfur. Combustion of such fuels can result in increased deposit formation and superheater corrosion. These problems can be reduced by using a sulfur containing additive, such as ammonium sulfate, which reacts with the alkali chlorides and forms less corrosive sulfates. Ammonium sulfate injection together with a so-called in situ alkali chloride monitor (IACM) is patented and known as "ChlorOut". IACM measures the concentrations of alkali chlorides (mainly KCl in biomass combustion) at superheater temperatures. Tests with and without spraying ammonium sulfate into the flue gases have been performed in a 96MW(th)/25MW(e) circulating fluidized bed (CFB) boiler. The boiler was fired mainly with bark and a chlorine containing waste. KCl concentration was reduced from more than 15 ppm to approximately 2 ppm. during injection of ammonium sulfate. Corrosion probe measurements indicated that both deposit formation and material loss due to corrosion were decreased using the additive. Analysis of the deposits showed significantly higher concentration of sulfur and almost no chlorine in the case with ammonium sulfate. Results from impactor measurements supported that KCl was sulfated to potassium sulfate by the additive. (C) 2007 Elsevier B.V. All rights reserved.

  • 272.
    Broström, Markus
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kassman, Håkan
    Helgesson, Anna
    Berg, Magnus
    Andersson, Christer
    Backman, Rainer
    Nordin, Anders
    Sulphation of Corrosive Alkali Chlorides by Ammonium Sulphate in a Biomass Fired CFB Boiler2006In: Impacts of Fuel Quality on Power Production, Snowbird, Utah, USA, 2006Conference paper (Other academic)
  • 273.
    Brunberg, Marike
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    User optimized design of handheld medical devices -applications and casing2010Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
  • 274.
    Brundin, Carl
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Alternative energy concepts for Swedish wastewater treatment plants to meet demands of a sustainable society2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This report travels through multiple disciplines to seek innovative and sustainable energy solutions for wastewater treatment plants. The first subject is a report about increased global temperatures and an over-exploitation of natural resources that threatens ecosystems worldwide. The situation is urgent where the current trend is a 2°C increase of global temperatures already in 2040. Furthermore, the energy-land nexus becomes increasingly apparent where the world is going from a dependence on easily accessible fossil resources to renewables limited by land allocation. A direction of the required transition is suggested where all actors of the society must contribute to quickly construct a new carbon-neutral resource and energy system. Wastewater treatment is as required today as it is in the future, but it may move towards a more emphasized role where resource management and energy recovery will be increasingly important.

    This report is a master’s thesis in energy engineering with an ambition to provide some clues, with a focus on energy, to how wastewater treatment plants can be successfully integrated within the future society. A background check is conducted in the cross section between science, society, politics and wastewater treatment. Above this, a layer of technological insights is applied, from where accessible energy pathways can be identified and evaluated.

    A not so distant step for wastewater treatment plants would be to absorb surplus renewable electricity and store it in chemical storage mediums, since biogas is already commonly produced and many times also refined to vehicle fuel. Such extra steps could be excellent ways of improving the integration of wastewater treatment plants into the society.

    New and innovative electric grid-connected energy storage technologies are required when large synchronous electric generators are being replaced by ‘smaller’ wind turbines and solar cells which are intermittent (variable) by nature. A transition of the society requires energy storages, balancing of electric grids, waste-resource utilization, energy efficiency measures etcetera… This interdisciplinary approach aims to identify relevant energy technologies for wastewater treatment plants that could represent decisive steps towards sustainability.

  • 275.
    Brus, Elisabet
    et al.
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Öhman, Marcus
    Umeå University.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics. Umeå University, Faculty of Science and Technology, Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Mechanisms of bed agglomeration during fluidized-bed combustion of biomass fuels2005In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 19, no 3, p. 825-832Article in journal (Refereed)
    Abstract [en]

    The major ash-related problem encountered in fluidized beds is bed agglomeration, which, in the worst case, may result in total defluidization of the bed and unscheduled downtime. Because of the special ash-forming constituents of biomass fuels, several of these fuels have been shown to be especially problematic. Despite the frequent reporting, a precise and quantitative knowledge of the bed agglomeration process during fluidized bed combustion of biomass fuels has not yet been presented. Bed sampling versus operation time was performed in four different biomass-fired full-scale fluidized beds, as well as during controlled fluidized bed agglomeration tests in bench-scale testing of five representative biomass fuels. The bed materials and agglomerates were further analyzed using scanning electron microscopy, coupled with energy-dispersive spectroscopy SEM/EDS, to determine the characteristics of the formed bed particle layers. For typical wood fuels, coating-induced agglomeration with subsequent attack reaction and diffusion by calcium into the quartz was identified to be the dominating bed agglomeration mechanism. Low-melting calcium-based silicates (including minor amounts of, for example, potassium) were formed with subsequent viscous-flow sintering and agglomeration. For high-alkali-containing biomass fuels, direct attack of the quartz bed particle by potassium compounds in a gas or aerosol phase formed a layer of low-melting potassium silicate. Thus, formation and subsequent viscous-flow sintering and agglomeration seemed to be the dominating agglomeration mechanism for these fuels.

  • 276.
    Brus, Elisabet
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Öhman, Marcus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hedman, Henry
    Energy Technology Centre, Piteå, Sweden.
    Eklund, Anders
    Bed agglomeration characteristics of biomass fuels using blast-furnace slag as bed material2004In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 18, no 4, p. 1187-1193Article in journal (Refereed)
    Abstract [en]

    Agglomeration of bed material may cause severe operating problems during fluidized bed combustion. The attack or coating layers that are formed on the bed particles during combustion play an important role in the agglomeration process. To reduce bed agglomeration tendencies, alternative bed materials may be used. In this paper, bed agglomeration characteristics during the combustion of biomass fuels using a relatively new bed material (iron blast-furnace slag) as well as ordinary quartz sand were determined. Controlled agglomeration tests lasting 40 h, using five representative biomass fuels (bark, olive residue, peat, straw, and reed canary grass) were conducted in a bench-scale fluidized bed. The bed materials and agglomerates were analyzed using SEM/EDS and X-ray diffraction. Chemical equilibrium calculations were performed to interpret the experimental findings. The results showed that blast-furnace slag had a lower tendency to agglomerate than quartz sand for most of the fuels. The quartz particles showed an inner attack layer more often than did the blast-furnace slag. The blast-furnace slag had a lower tendency to react with elements from the fuel. The outer coating layer had similar characteristics and thickness for both bed materials when the same fuel was combusted. However, the inner attack layer thickness was larger for quartz particles. SEM/EDS analyses of the agglomerates showed that the inner Ca-K-silicate-rich attack layer was responsible for the agglomeration of quartz sand. The composition of blast-furnace slag agglomerate was similar to the outer coating layer. Chemical equilibrium calculations showed that the original composition of the blast-furnace slag was close to the equilibrium composition, and hence there was no major driving force for reactions between that bed material and K and Ca from the fuel. The homogeneous silica-rich attack layer (with a low melting temperature) was not formed to the same extent for blast-furnace slag, thus explaining the lower bed agglomeration tendency.

  • 277.
    Bränberg, Agneta
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Hur startar man ett helt nätbaserat utbildningsprogram?: IngOnline som ett exempel på COI för blended learning2009In: Undervisning på tvären: student och lärarerfarenheter : den nionde universitetspedagogiska konferensen 25-26 februari 2009 : konferensrapport / [ed] Erik Lindenius, Umeå, 2009, p. i-xConference paper (Other academic)
    Abstract [sv]

    Denna artikel kommer att beskriva hur vi, en grupp på åtta personer från åtta olika högskolor, jobbat tillsammans för att utveckla och starta ett helt nätbaserat högskoleingenjörsprogram i datateknik/elektroteknik. Arbetsmetoden som vi använt har (sett i en backspegel) vilat tungt på att vi kunnat träffas rent fysiskt för att få en social interaktion och däremellan kunnat ha olika typer av täta kontakter av mer virtuell natur där tekniken har varit till stor hjälp. Man kan uttrycka det som att vi använt så kallad Blended Learning. Formen för samverkansgruppen skulle man kunna beskriva som ett Community of Inquiry, dvs en grupp människor som samverkar för att bygga kunskap.

    Artikeln kommer att beskriva arbetsmetoden, hur vår grupp såg ut, vad vi har fått för erfarenheter av att jobba på detta vis, hur programmet blev och vad man kan ta med sig om man tänker starta ett nytt program på samma sätt som vi gjort.

  • 278.
    Bränberg, Agneta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Holmgren, Ulf
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Attityder och förmåga! Utbildning också för den högra hjärnhalvan: Erfarenheter från en inledande kurs på ett ingenjörsprogram2007In: Utsikter, insikter, avsikter: universitetspedagogisk konferens i Umeå 27 – 28 februari 2007 / [ed] Mohammad Fazlhashemi och Thomas Fritz, Umeå: Umeå Universitet, Universitetspedagogiskt centrum , 2007, p. 41-54Conference paper (Other academic)
    Abstract [sv]

    Undervisningssituationen är ett samspel mellan lärare och student. Studentens framgång i studierna är i hög grad beroende av hur denna relation etableras och hur den utvecklas under studietiden. Inte minst viktigt är att vara uppmärksam på hur relationen etableras och där är lärarens attityd till studenten av betydelse. Att i någon mån släppa de ämnesstyrande kraven och redan tidigt i utbildningen skapa situationer där kreativiteten och de yrkesmässiga målen för utbildningen får dominera ökar studenternas vilja att arbeta aktivt i och med sin utbildning. Det ger utrymme för lärstilar som inte enbart bygger på teoretiskt kunskapsinhämtande och framförallt får vi som lärare en mycket roligare, mer utvecklande och mer spännande arbetssituation. Med denna artikel vill vi visa på möjligheter att med framgång och mycket tidigt i utbildningen arbeta projektorienterat och yrkesnära. Rapporten redovisar ett försök att mycket tidigt i utbildningen arbeta med ingenjörsmässiga frågeställningar utifrån studenternas erfarenheter och värderingar.

  • 279.
    Bränberg, Agneta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Holmgren, Ulf
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Forskningsanknytning av grundutbildning: en praktisk analysmetod2015In: 5:e Utvecklingskonferensen för ingenjörsutbildningar: Proceedings, Uppsala: Uppsala universitet, 2015, p. 51-55Conference paper (Other academic)
    Abstract [sv]

    Forskningsanknytning av grundutbildning kan och ska inte enbart vara fokuserad på att våra lärare är forskare. Det är så mycket mer kopplat till den. Som så många gånger när världen ser komplex ut är det lätt att man förenklar den alltför mycket. I denna artikel försöker vi vidga begreppen. Vi presenterar en analysmodell i form av ett fyrfältsdiagram, som kan byggas ut med en progressionsskala. Modellen som presenteras är ett verktyg som kan fungera både för analys av och som utgångspunkt för diskussioner om forskningsanknytning av ingenjörsutbildningar.

  • 280.
    Bränberg, Agneta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Holmgren, Ulf
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kursdesign med utgångspunkt i utveckling av kreativitet, kritiskt förhållningssätt och initiativförmåga2011In: 3e Utvecklingskonferensen för Sveriges ingenjörsutbildningar. 30 november-1 december 2011, 2011, p. 112-116Conference paper (Other academic)
    Abstract [sv]

    Kursen Analog elektronik 15hp är den första renodlade ämneskurs som studenterna på högskoleingenjörsprogrammet i Elektronik och datorteknik möter och den ges under senare delen av höstterminen i första årskursen. Kursen är central på programmet dels ämnesmässigt men framförallt genom önskemålet att etablera ingenjörsmässiga arbetsformer och ett ingenjörsmässigt förhållningssätt i kommande kurser på programmet. Tre aspekter bildar bas för kursens målbeskrivning

     -Kunskapsbasen definierad av klassisk analogiteknik och elementära elektroniska system

    -Färdighetsmålen med fokus på konstruktion, experiment, simulering och analys

    -Formerande av en attityd till lärande där kreativitet, lagarbete och kritiskt förhållningssätt står i centrum

    I presentationen diskuteras hur arbetsmetodik, kursinnehåll och examination kan utformas i syfte att stödja samtliga tre måldimensioner och hur motivation, personligt ansvarstagande och professionellt förhållningssätt kan utvecklas genom en medveten utformning av läraktiviteter.

  • 281. Bränberg, Agneta
    et al.
    Holmgren, Ulf
    Chrsitensen, Bendt
    Eklund, Robert
    Olofsson, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ramstedt, Madeleine
    Undervisningens forskningsanknytning2014Conference paper (Refereed)
  • 282.
    Bränberg, Agneta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Holmgren, Ulf
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Gulliksson, Håkan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Didaktik för ingenjörslärare2013In: 4:e Utvecklingskonferensen för Sveriges Ingenjörsutbildningar, 2013, p. 9-11Conference paper (Other academic)
    Abstract [sv]

    Didaktik är vetenskapen om alla faktorer sompåverkar undervisningen och dess innehåll, och sätter fokus pålärande och hur lärande organiseras. Didaktik berör alltså vadläraren skall tänka på vid undervisning, dess mål och medel samtsambandet dem emellan. Ämnesdidaktiken fokuserar på vilkavillkor som är av betydelse för lärandet av ett specifikt ämne påolika nivåer, exempelvis matematikdidaktik eller språkdidaktik.Målet för professionsutbildningar (exempelvisingenjörsutbildningarna) skiljer sig från ämnesorienteradeutbildningar genom att fokus ligger på yrkesrollen, vad denexaminerade studenten ÄR, vad den GÖR och kanske i tredjehand vad han eller hon KAN. Detta påverkar hur vi somingenjörslärare hanterar de didaktiska frågorna VARFÖR, HURoch VAD? Rundabordsdiskussionen berör frågeställningar kringutvecklandet av en ingenjörsdidaktik samt hinder ochmöjligheter för denna didaktik att få ett större genomslag i dendagliga didaktiska praktiken. Diskussionen tar avstamp i ennyutkommen bok ”Didaktik för ingenjörslärare” [1].

  • 283.
    Bränberg, Agneta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Holmgren, Ulf
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Gulliksson, Håkan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Didaktik för ingenjörslärare: konsten och glädjen med att utbilda ingenjörer2013 (ed. 1)Book (Other academic)
  • 284.
    Bränberg, Agneta
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Winka, Katarina
    Umeå University, Faculty of Arts, Centre for Teaching and Learning (UPC).
    Tänk vad vi är bra: pedagogiska portföljer ger ringar på vattnet2013In: Reformation, revolution, evolution: universitetslärandet ur ett tidsperspektiv / [ed] Erik Lindenius, Umeå: Umeå universitet , 2013, p. 123-138Conference paper (Other academic)
  • 285.
    Bräne, Arvid
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    User Experience Design for Children: Developing and Testing a UX Framework2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Designing good digital experiences for children can be difficult; designers have to consider children's cognitive and motor skill limitations, understand their target audience, create something entertaining and educational, comply with national and international jurisdiction, and at the same time appeal to parents. We set out to create a general framework which designers and developers can use as a foundation and testing ground for their digital products in the field of user experience.

    The methods used during the thesis include interviews, literature studies, user testing, case studies, personas, prototyping, and more. The results created are primarily user experience guidelines packaged in a Theoretical Framework, user testing conclusions, along with suggestions on improving the current Lego Star Wars: Force Builders application, a few in the form of prototypes.

  • 286.
    Brännback, Andreas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    FTTX-Analysverktyg anpassat för Telias nät2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A tool for analyzing the status of Fiber to the X (FTTX) customers in Telia’s network has been programmed in the Python programming language. The system consists of a module divided structure where analysis functions of similar types are bundled into module files. The system is designed to be easily further developed by adding more analysis modules in future projects. To perform an analysis on a specific customer, the system retrieves technical data parameters from the switch which the customer is connected to, and compares these parameters against predetermined values to find deviations. Simple Network Management Protocol (SNMP) and Telnet are the primary protocols used to retrieve data. Hypertext Transfer Protocol (HTTP) is used to transfer data as system input and output. The result of an analysis is sent as Extensible Markup Language (XML) back to the server that originally requested the start of an analysis. The XML reply contains technical data parameters describing the customer’s connection status and an analytical response based on these technical parameters. The amount of data presented in the XML response varies slightly depending on the type of switch the customer is connected to. Switches of older hardware types generally presents less customer port data compared to more modern switches. Less customer port data leads to poor detail in the analytical response, and therefore, this analysis tool is better suited to the modern switches found in Telia's network.

  • 287.
    Brännström, Emil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Underlag för kommunal- respektive gårdsbaserad biogasanläggning.2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 288.
    Brännvall, Evelina
    et al.
    Luleå Tekniska Universitet.
    Nilsson, Malin
    Luleå Tekniska Universitet.
    Sjöblom, Rolf
    Luleå Tekniska Universitet.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kumpiene, Jurate
    Luleå Tekniska Universitet.
    Effect of residue combinations on plant uptake of nutrients and potentially toxic elements2014In: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 132, p. 287-295Article in journal (Refereed)
    Abstract [en]

    The aim of the plant pot experiment was to evaluate potential environmental impacts of combined industrial residues to be used as soil fertilisers by analysing i) element availability in fly ash and biosolids mixed with soil both individual and in combination, ii) changes in element phytoavailability in soil fertilised with these materials and iii) impact of the fertilisers on plant growth and element uptake.

    Plant pot experiments were carried out, using soil to which fresh residue mixtures had been added. The results showed that element availability did not correlate with plant growth in the fertilised soil with. The largest concentrations of K (3534 mg/l), Mg (184 mg/l), P (1.8 mg/l), S (760 mg/l), Cu (0.39 mg/l) and Zn (0.58 mg/l) in soil pore water were found in the soil mixture with biosolids and MSWI fly ashes; however plants did not grow at all in mixtures containing the latter, most likely due to the high concentration of chlorides (82 g/kg in the leachate) in this ash. It is known that high salinity of soil can reduce germination by e.g. limiting water absorption by the seeds. The concentrations of As, Cd and Pb in grown plants were negligible in most of the soils and were below the instrument detection limit values.

    The proportions of biofuel fly ash and biosolids can be adjusted in order to balance the amount and availability of macronutrients, while the possible increase of potentially toxic elements in biomass is negligible seeing as the plant uptake of such elements was low.

  • 289. Buga, Sergei
    et al.
    Blank, Vladimir
    Bagramov, Rustem
    Dubitsky, Gennadii
    Fransson, Åke
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Serebryanaya, Nadejda
    Sundqvist, Bertil
    Umeå University, Faculty of Science and Technology, Physics.
    Thermal stability of superhard and ultrahard fullerites2000In: Proceedings of International Conference on Engineering and Technological Sciences 2000 (ICETS-2000), vol. 1, Beijng: Chinese Academy of Engineering: New World Press , 2000, p. 505-511Conference paper (Refereed)
    Abstract [en]

    The thermal stability of superhard and ultrahard carbon phases synthesized from C60 and C70 fullerenes under pressure in the range 9.5-13 GPa and temperature between 670 and 1850 K was investigated by DSC in the range 260-640 K and TGA up to 1200 K. Endothermal heat effects were observed with a peak maximum just below 540 K, a temperature characteristic for breakdown of (2+2) intermolecular links in dimers, 1D and 2D polymers. Exothermal effects, starting from 380 K, were observed for the first time in polymeric fullerenes. These effects are attributed to relaxation processes and to breakdown of other types of intermolecular bonds.

  • 290. Buga, Sergei G.
    et al.
    Blank, Vladimir D.
    Dubitsky, Gennadii A.
    Serebryanaya, Nadejda R.
    Fransson, Åke
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Wågberg, Thomas
    Umeå University, Faculty of Science and Technology, Physics.
    Sundqvist, Bertil
    Umeå University, Faculty of Science and Technology, Physics.
    Synthesis of superhard 3D-polymeric C60 fullerites from rhombohedral 2D-polymer by high-pressure-high-temperature treatment.2003In: High Pressure Research vol. 23, issue 3: Proceedings of the 40th European High Pressure Research Group Meeting on Advances in High Pressure Research (EHPRG'40), London: Taylor & Francis , 2003, p. 259-264Conference paper (Refereed)
    Abstract [en]

    Rhombohedral C60 polymer was subjected to high-pressure-high-temperature treatment at P =13 GPa, T =620-1620 K. After quenching, crystalline and disordered structures with densities in the range of 2.1-2.9 g cm-1 were obtained. The structures of the samples have been investigated by powder X-ray diffraction and Raman scattering. DSC analysis showed a transformation of the polymeric structure into monomeric on annealing in the range 400-640 K. The temperature dependence of the electrical resistance of samples with disordered structure was measured in the range 2.5-300K. For different samples, the conductivity was proportional to T1/2, T3/2, T4 and exp(-1/T1/4).

  • 291. Buga, Sergei G.
    et al.
    Blank, Vladimir D.
    Fransson, Åke
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Serebryanaya, Nadejda R.
    Sundqvist, Bertil
    Umeå University, Faculty of Science and Technology, Physics.
    DSC study of annealing and phase transformations of C60 and C70 polymerized under pressures in the range 9.5 - 13 GPa.2002In: Journal of Physics and Chemistry of Solids, ISSN 0022-3697, E-ISSN 1879-2553, Vol. 63, no 2, p. 331-343Article in journal (Refereed)
    Abstract [en]

    C60 and C70 fullerenes polymerized under pressures between 9.5 and 13 GPa and temperatures between 670 and 1850 K were investigated by differential scanning calorimetry (DSC) in the range 240–640 K. Endothermal heat effects were observed with a peak maximum just below 540 K, a temperature characteristic for breakdown of (2+2) intermolecular links in dimers, 1D and 2D polymers. Exothermal effects, starting from 380 K, were observed for the first time in polymeric fullerenes. These effects are attributed to relaxation processes and to breakdown of other types of intermolecular bonds such as common four-sided rings and (3+3) interlinks.

  • 292. Buga, Sergei G.
    et al.
    Fransson, Åke
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Serebryanaya, Nadejda R.
    Sundqvist, Bertil
    Umeå University, Faculty of Science and Technology, Physics.
    Blank, Vladimir D.
    Dubitsky, Gennadii A.
    Dissociation energy of 3D-polymeric C60: Calorimetric study and structural analysis2001In: Electronic Properties of Novel Materials - Science and Technology of Molecular Nanostructures: Proceedings of the XV International Winter School on Electronic Properties of Novel Materials, Kirchberg 2001, Melville, NY: American Institute of Physics , 2001, p. 49-53Conference paper (Refereed)
    Abstract [en]

    Annealing of 2D- and 3D-polymeric C[sub60] fullerene obtained under pressures of 9.5 and 12.5 GPa and temperatures of 670 and 770 K has been investigated by DSC in the range 240–640 K. An endothermal heat effect was observed with a peak maximum just below 540 K, a temperature characteristic for breakdown of (2+2) intermolecular links in dimers, 1D and 2D polymers. Exothermal effects, starting from 380 K, were observed for the first time in polymeric fullerenes. These effects are attributed to relaxation processes and to breakdown of other types of intermolecular bonds such as common four-sided rings and (3+3) interlinks.

  • 293.
    Bugaytsova, Jeanna A.
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Björnham, Oscar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Swedish Defence Research Agency, 906 21 Umeå, Sweden.
    Chernov, Yevgen A.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Gideonsson, Pär
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Henriksson, Sara
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Mendez, Melissa
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Sjöström, Rolf
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Mahdavi, Jafar
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. School of Life Sciences, CBS, University of Nottingham, NG7 2RD Nottingham, UK.
    Shevtsova, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Ilver, Dag
    Moonens, Kristof
    Quintana-Hayashi, Macarena P.
    Moskalenko, Roman
    Aisenbrey, Christopher
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Bylund, Göran
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Schmidt, Alexej
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Åberg, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Brännström, Kristoffer
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Koeniger, Verena
    Vikström, Susanne
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Rakhimova, Lena
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Hofer, Anders
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Ögren, Johan
    Umeå University, Faculty of Medicine, Department of Odontology.
    Liu, Hui
    Goldman, Matthew D.
    Whitmire, Jeannette M.
    Åden, Jörgen
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Younson, Justine
    Kelly, Charles G.
    Gilman, Robert H.
    Chowdhury, Abhijit
    Mukhopadhyay, Asish K.
    Nair, G. Balakrish
    Papadakos, Konstantinos S.
    Martinez-Gonzalez, Beatriz
    Sgouras, Dionyssios N.
    Engstrand, Lars
    Unemo, Magnus
    Danielsson, Dan
    Suerbaum, Sebastian
    Oscarson, Stefan
    Morozova-Roche, Ludmilla A.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Olofsson, Anders
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Gröbner, Gerhard
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Holgersson, Jan
    Esberg, Anders
    Umeå University, Faculty of Medicine, Department of Odontology.
    Strömberg, Nicklas
    Umeå University, Faculty of Medicine, Department of Odontology.
    Landström, Maréne
    Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Eldridge, Angela M.
    Chromy, Brett A.
    Hansen, Lori M.
    Solnick, Jay V.
    Linden, Sara K.
    Haas, Rainer
    Dubois, Andre
    Merrell, D. Scott
    Schedin, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Remaut, Han
    Arnqvist, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Berg, Douglas E.
    Boren, Thomas
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Helicobacter pylori Adapts to Chronic Infection and Gastric Disease via pH-Responsive BabA-Mediated Adherence2017In: Cell Host and Microbe, ISSN 1931-3128, E-ISSN 1934-6069, Vol. 21, no 3, p. 376-389Article in journal (Refereed)
    Abstract [en]

    The BabA adhesin mediates high-affinity binding of Helicobacter pylori to the ABO blood group antigen-glycosylated gastric mucosa. Here we show that BabA is acid responsive-binding is reduced at low pH and restored by acid neutralization. Acid responsiveness differs among strains; often correlates with different intragastric regions and evolves during chronic infection and disease progression; and depends on pH sensor sequences in BabA and on pH reversible formation of high-affinity binding BabA multimers. We propose that BabA's extraordinary reversible acid responsiveness enables tight mucosal bacterial adherence while also allowing an effective escape from epithelial cells and mucus that are shed into the acidic bactericidal lumen and that bio-selection and changes in BabA binding properties through mutation and recombination with babA-related genes are selected by differences among individuals and by changes in gastric acidity over time. These processes generate diverse H. pylori subpopulations, in which BabA's adaptive evolution contributes to H. pylori persistence and overt gastric disease.

  • 294.
    Bugaytsova, Jeanna
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Björnhamn, Oscar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Henriksson, Sara
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Johansson, Pär
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Mendez, Melissa
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Sjöström, Rolf
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Brännström, Kristoffer
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Aisenbrey, Christopher
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Shevtsova, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Bylund, Göran
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Mahdavi, Jafar
    Ögren, Johan
    Ilver, Dag
    Gilman, Robert H
    Chowdhury, Abhijit
    The Swedish Institute for Control, Solna, Swede.
    Mukhopadhyay, Asish K
    Engstrand, Lars
    Oscarson, Stefan
    Kelly, Charles G
    Younson, Justine S
    Odenbreit, Stefan
    Solnick, Jay
    Gröbner, Gerhard
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Haas, Rainer
    Dubois, Andre
    Schedin, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Berg, Douglas E
    Arnqvist, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Borén, Thomas
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    pH regulated H. pylori adherence: implications for persistent infection and diseaseManuscript (preprint) (Other academic)
    Abstract [en]

    Helicobacter pylori’s BabA adhesin binds strongly to gastric mucosal ABH/Leb glycans on the stomach epithelium and overlying mucus, materials continuously shed into the acidic gastric lumen. Here we report that this binding is acid labile, acid inactivation is fully reversible; and acid lability profiles vary with BabA sequence and correlate with disease patterns. Isogenic H. pylori strains from the gastric antrum and more acidic corpus were identified that differed in acid lability of receptor binding and in sequence near BabA’s carbohydrate binding domain. We propose that reversible acid inactivation of receptor binding helps H. pylori avoid clearance by mucosal shedding, and that strain differences in acid lability affect tissue tropism and the spectrum of associated gastric diseases.

  • 295.
    Bugaytsova, Jeanna
    et al.
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Chernov, Yevgen A
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Gideonsson, Pär
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Mendez, Melissa
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Henriksson, Sara
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. Umeå University, Faculty of Medicine, Department of Molecular Biology (Faculty of Medicine).
    Mahdavi, Jafar
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. School of Life Sciences, CBS, University of Nottingham, Nottingham, UK..
    Quintana-Hayashi, Macarena
    Department of Biochemistry and Cell biology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden..
    Shevtsova, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Sjöström, Rolf
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Moskalenko, Roman
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. Department of Pathology, Medical Institute, State University, Sumy, Ukraine.
    Aisenbrey, Christopher
    Umeå University, Faculty of Science and Technology, Department of Chemistry. Université de Strasbourg, Institut de Chimie, Strasbourg, France.
    Moonens, Kristof
    Structural and Molecular Microbiology, VIB Department of Structural Biology, Belgium.
    Björnham, Oscar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. FOI Totalförsvarets Forskningsinstitut, Umeå, Sweden..
    Brännström, Kristoffer
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Bylund, Göran
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Königer, Verena
    Max von Pettenkofer Institute of Hygiene and Medical Microbiology, LMU, Munich, Germany.
    Vikström, Susanne
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Schmidt, Alexej
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics. Umeå University, Faculty of Medicine, Department of Medical Biosciences.
    Rakhimova, Lena
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Hofer, Anders
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Ögren, Johan
    Umeå University, Faculty of Medicine, Department of Odontology.
    Ilver, Dag
    Department of Biochemistry and Cell biology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Liu, Hui
    Department of Medicine, USUHS, Bethesda, MD, USA.
    Goldman, Matthew
    Department of Pediatrics, USUHS, Bethesda, MD, USA.
    Whitmire, Jeannette M
    Department of Microbiology and Immunology, USUHS, Bethesda, MD USA.
    Kelly, Charles G
    King's College London, Dental Institute, London, UK.
    Gilman, Robert H
    Department of International Health, John Hopkins School of Public Health, Baltimore, MD, USA.
    Chowdhury, Abhijit
    Centre for Liver Research, School of Digestive and Liver Diseases, Institute of Post Graduate Medical Education & Research, Kolkata, India.
    Mukhopadhyay, Asish K
    Division of Bacteriology, National Institute of Cholera and Enteric Diseases, Kolkata, India.
    Nair, Balakrish G
    Translational Health Science and Technology Institute, Haryana, India.
    Papadakos, Konstantinos S
    Hellenic Pasteur Institute, Athens, Greece.
    Martinez-Gonzalez, Beatriz
    Hellenic Pasteur Institute, Athens, Greece.
    Sgouras, Dionyssios N
    Hellenic Pasteur Institute, Athens, Greece.
    Engstrand, Lars
    Department of Microbiology, Tumor and Cell Biology, Karolinska Institutet, Stockholm, Sweden.
    Unemo, Magnus
    Department of Laboratory Medicine, Microbiology, Örebro University Hospital, Örebro, Sweden.
    Danielsson, Dan
    Department of Laboratory Medicine, Microbiology, Örebro University Hospital, Örebro, Sweden.
    Sebastian, Suerbaum
    Institute for Medical Microbiology and Hospital Epidemiology Hannover Medical School, Hannover, Germany.
    Oscarson, Stefan
    Centre for Synthesis and Chemical Biology, School of Chemistry, University College Dublin, Dublin, Ireland.
    Morozova-Roche, Ludmilla
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Gröbner, Gerhard
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Holgersson, Jan
    Department of Clinical Chemistry and Transfusion Medicine, Sahlgrenska Academy, University of Gothenburg, Sahlgrenska University Hospital, Gothenburg, Sweden.
    Strömberg, Nicklas
    Umeå University, Faculty of Medicine, Department of Odontology.
    Esberg, Anders
    Umeå University, Faculty of Medicine, Department of Odontology.
    Eldridge, Angela
    Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento, CA, USA.
    Chromy, Brett A
    Department of Pathology and Laboratory Medicine, University of California Davis School of Medicine, Sacramento, CA, USA.
    Hansen, Lori
    Departments of Medical Microbiology and Immunology, Center for Comparative Medicine, University of California Davis, Davis, CA, USA.
    Solnick, Jay
    Departments of Medical Microbiology and Immunology, Center for Comparative Medicine, University of California Davis, Davis, CA, USA.
    Haas, Rainer
    Max von Pettenkofer Institute of Hygiene and Medical Microbiology, LMU Munich, Munich, Germany.
    Schedin, Staffan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lindén, Sara K
    Department of Biochemistry and Cell biology, Sahlgrenska Academy, University of Gothenburg, Gothenburg, Sweden.
    Dubois, Andre
    Department of Medicine, USUHS, Bethesda, MD, USA.
    Merrell, D. Scott
    Department of Microbiology and Immunology, USUHS, Bethesda, MD, USA.
    Remaut, Han
    Structural and Molecular Microbiology, VIB Department of Structural Biology, VIB, Brussels, Belgium.
    Arnqvist, Anna
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Berg, Douglas E
    Department of Medicine, University of California San Diego, La Jolla, CA, USA.
    Borén, Thomas
    Umeå University, Faculty of Medicine, Department of Medical Biochemistry and Biophysics.
    Acid Responsive Helicobacter pylori Adherence: Implications for Chronic Infection and DiseaseManuscript (preprint) (Other academic)
  • 296.
    Burck, Robin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    ENERGIEFFEKTIVISERING AV VENTILATIONSYSTEM I AITIK, BOLIDEN2015Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    The mine of Aitik is the largest open cast mine in Sweden that refines chalcopyrite. The chalcopyrite is being transported from the open cast mine beneath through a system of underground tunnels to a refinery above ground. There is a ventilation system in the tunnels that is controlled without knowledge of the requirement of ventilation’s force. Boliden has the intention of doing energy saving’s within the corporation. One alternative to save energy is to steer the ventilation. There’s an application called “Ventilation on demand” that steers the airflow of ventilation systems, which can be implemented in the current steering system 800xA. The concept of the application is to minimize the use of energy and both the application and steering system is a product of ABB. Before the implementation of the application a pilot study is needed to chart the airflow based on the requirement to sustain good working environment in the tunnels. The pilot study will contain a situation analysis and a series of measurements with different ventilation speeds. The result of measurement will tell how the ventilation speed affects the air quality in the tunnels and energy use of fans and district heating. The pilot study will also contain the result of cost- and energy savings by installing the application. ‘  The ventilation system contains five fans and two of them have frequency inverters. The air that is forced down to the system of tunnels is heated by district heating trough heating batteries. Skellefteå Kraft is the supplier of the district heating and the pellet boiler is located within the mining area. The situation analysis will be a reference to compare the series of measurements and present the possibilities of cost- and energy savings regarding the working environment in the tunnels.  The result demonstrates the possibilities of making energy savings up to sixty percent and still have a good working environment. The result also demonstrate that “Ventilation on demand” has a short payback time.

  • 297.
    Burlin, Jesper
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Geoenergi med och utan värmepump2017Independent thesis Advanced level (professional degree), 300 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete utfördes på uppdrag av Umeå Kommun. Uppgiften bestod av att utvärdera dagens användning av en borrhålsbrunn samt undersöka vad som är det optimala användningsområdet för borrhålsbrunnen. Borrhålsbrunnen används i dagsläget för att förvärma samt kyla utomhusluft in till kontorsbyggnaden Kubens ventilationsaggregat.

    Ventilationens förvärmning består av två delar, en markkanal och ett geoenergibatteri. Viktiga parametrar hos förvärmningen analyserades med hjälp av mätvärden för temperatur och flöde. Resultaten jämfördes därefter med alternativet att använda borrhålsbrunnen tillsammans med en värmepump. Då borrhålsbrunnens kapacitet inte var tillräcklig för att klara byggnadens hela uppvärmningsbehov, undersöktes det hur en värmepump skulle kunna köras i kombination med fjärrvärme. Två driftstrategier, Bas och Kapatoppar, undersöktes. Bas leverar en basproduktion under hela vinterperioden medan Kapatoppar startar vid -6°C för att sänka effekttoppar.

    Utvärderingen av förvärmningen visade att geoenergibatteriet är mer kompatibelt med ventilationsaggregat av VAV-typ (Variable Air Volume) än vad markkanalen är. Däremot är inte förvärmning i kombination med roterande värmeväxlare ett bra koncept för byggnaden som den används idag. På grund av att förvärmningen är placerad före den roterande värmeväxlaren så är bara 15-20 % av förvärmningseffekterna energibesparande. Detta kombinerat med en optimerad drift av aggregatet sett till tidsstyrning och behovsstyrning av flöde gör att förvärmningen har en liten påverkan både på byggnadens maximala effektbehov och totala energibehov.

    Att köra värmepump i kombination med fjärrvärme för uppvärmning var ekonomiskt lönsamt främst på grund av att värmepumpen kunde kapa byggnadens effektoppar. Kostnaden för storleken på den abonnerade effekten uppgår idag till drygt 40 % av den totala fjärrvärmekostnaden. Dagens relation mellan el- och fjärrvärmepriser bidrog naturligtvis också till att värmepumpsalternativet var lönsamt. För de undersökta förutsättningarna så blev paybacktiden för en värmepump med den lönsammaste driftstrategin, Bas, 4,4 år.

  • 298.
    Burman, Sebastian
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energiuppföljning på två flerbostadshus i centrala Skellefteå.2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    One third of Sweden's energy use is used by residential and commercial buildings, of which nearly 60 % go to heating. Opportunities are great for using energy more efficiently and there is a great potential to save energy by improving the construction of the building. The EU places higher demands on energy use and means that monitoring of energy use is becoming increasingly important. From 2021, all new production of buildings in EU Member States will be "close to zero energy houses". The definition of "near zero energy house" has not yet been established in Sweden, but in a throw-out of BBR is the requirement to tighten by 40 % discussed. Efforts to get more energy-efficient buildings are under way and are being carried out in close collaboration with BBR.

     

    This degree project has been carried out on behalf of Skebo, where the goal is to establish the real specific energy use in operation for two properties in Skellefteå, Ringduvan and Odenskrapan. Compare and analyze deviations from projected specific energy use. Ringduvan was ready for occupation in spring 2014 and Odenskrapan in early 2016.Both buildings have electricity and district heating from Skellefteå Kraft. Ringduvan is projected by NCC and Oden of Lindbergs Energi & VVS AB.

     

    Sveby ("Standardize and Verify Energy Performance in Buildings") is a development program run by actors in the construction and real estate industry. Svebys aim is to develop an industry standard that increases the accuracy of the project between projected and real energy use. With increased knowledge of user-related use, a standardized approach, energy monitoring and enhanced cooperation between actors, the goal is to reduce the deviations. Operators in the industry may choose to enter into a Sveby agreement, which includes a common method of procurement, design and verification.

     

    The projected specific energy use for Ringduvan is 76 kWh/m2,year and the real is 101 kWh/m2,year. Odenskrapan projected is 53 kWh/m2,year and the real is 93 kWh/ m2,year. That is, the specific energy use exceeds the estimated energy consumption by 33 % for Ringduvan and 75 % for Odenskrapan. This means that much more district heating and real estate is needed than expected.

     

    In general, potential causes of higher energy use have been identified. But nothing has been confirmed and more work is required against the buildings in order to compare and identify the exact reasons.

  • 299.
    Burman, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energianalys av MVG-gallerian, samt en jämförelse av beräkningsprogram2013Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis has been carried out in the spring of 2013, on behalf of Sweco Systems in Umeå. The aim of this work was to evaluate the possibilities of using any energy simulation software in the work of mapping energy usage of existing facilities. In this study two of the softwares that is being used in the company are evaluated – VIP-Energy and IDA Indoor Climate and Energy.

    Initially a mapping of the energy usage was performed on the property Odin 12 in Umeå, which consists mainly of the mall MVG. The energy usage was then simulated with the two different softwares.

    The mapping of energy usage shows that the building has a low annually need of space heating. This is due to the fact that the consumption of electricity in the building is very high, which leads to very high internal loads and a low need for additional heating. For the same reason, a need of space cooling is present during the whole year.

    The evaluation of the two energy simulation softwares shows that VIP-Energy is a suitable program for energy mapping. The program is both simple and flexible which reduces the time needed for creating the model.  Considering the time for the actual calculations, VIP-Energy is the program that is by far the fastest.

  • 300.
    Bygdén, Olov
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Testpiloter i praktisk energieffektivisering: Visualisering och kommunikation2012Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta arbete har utförts på Skellefteå Kommuns fastighetsavdelning under hösten 2012 och även under början på 2013. Fastighetsavdelningen är ansvariga för bl.a. driften hos Skellefteå Kommuns byggnader och därmed också ansvariga för att minska energianvändningen hos dessa. Till år 2016 har Skellefteå Kommun som mål att åstadkomma en energieffektivisering på 20 % jämfört med utgångsåret 2009. Detta projekt har utförts som en del av detta energieffektiviseringsarbete.

     Projektet omfattar två olika mätperioder, under den andra av dessa mätperioder installerades visualiseringsskärmar hos de två berörda objekt som utvalts till detta projekt. På visualiseringsskärmarna visades sedan den momentana energiförbrukningen för att brukarna skulle kunna hålla koll på om förbrukningen ökade eller minskade sett till den senaste veckan. Två informationsträffar, en för varje arbetsplats, hölls också för att informera om projektet samt att ge tips på tänkbara förändringar i arbetsmetoderna som skulle kunna medföra minskad energiförbrukning och därigenom ett positiv resultat.

    Resultatet av detta projekt blev en mängd mätdata som har sammanställts och analyserats för att slutligen resultera i ett utfall i form av att det ena objektet minskade sin energiförbrukning med 1,7 % och det andra objektet med hela 24,2 %.

    Slutsatsen har därmed blivit att visualisering samt kommunikation kan vara ett tänkbart alternativ till att åstadkomma en minskad energianvändning och motivera brukare av lokaler att bli engagerade och bidra själva.

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