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  • 101.
    Bängtsson, Erik
    et al.
    Department of Information Technology, Uppsala University.
    Noreland, Daniel
    Department of Information Technology, Uppsala University.
    Berggren, Martin
    Department of Information Technology, Uppsala University.
    Shape optimization of an acoustic horn2003In: Computer Methods in Applied Mechanics and Engineering, ISSN 0045-7825, E-ISSN 1879-2138, Vol. 192, p. 1533-1571Article in journal (Refereed)
  • 102.
    Carlborg, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Exposure studies of refractory materials for biomass gasification2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Gasification is a technology mostly used to convert fossil feedstock to syngas. Biomass could be used as a feedstock instead but that puts different demands on, among other things, the materials in these reactors.

    In this work, two candidate materials for the inner lining in biomass gasifiers (63 and 85 weight percent Al2O3) have been exposed to three synthetic ashes, K2CO3-CaCO3-SiO2, K2CO3-CaCO3 and K2CO3 at 1050°C in CO2 atmosphere for 7 days in a muffle furnace to reproduce analogous chemical attack that would occur in a real gasifier. Samples were investigated with SEM-EDX for morphological and compositional effects and with XRD for crystalline phases at chosen distances from the exposed surface.

    A heterogeneous melt that prevented deep penetration of alkali was produced when Si was present in the ash composition. In the absence of Si, it turned out that only K was affecting the materials. K attacked the matrix and transported into the material and attacking grains. For the material containing more alumina potassium was found in continuously decreasing amounts down to 7-8 mm from the exposed surface. The other material showed a distinct border between affected and pristine matrix about 5 mm from the exposed surface. The affected part seemed to have been filled out and signs of expansion could be seen. The XRD analysis of the pristine and exposed refractories revealed significant differences. In the exposed ceramics the new phases; Leucite, Kalsilite, Kaliophilite, K(2-x)Al(2-x)SixO4 and Wollastonite were observed.

  • 103.
    Carlborg, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Refractory corrosion in biomass gasification2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    To stop the net emission of CO2 to the atmosphere, we need to reduce our dependency of fossil fuels. Although a switch to a bio-based feedstock hardly can replace the total amount of fossils used today, utilization of biomass does still have a role in a future in combination with other techniques. Valuable chemicals today derived from fossils can also be produced from biomass with similar or new technology. One such technique is the entrained flow gasification where biomass is converted into synthesis gas. This gas can then be used as a building stone to produce a wide range of chemicals.

    Slagging and corrosion problems are challenges presented by the ash forming elements in biomass during thermochemical energy conversion. The high temperature in the entrained flow process together with ash forming elements is creating a harsh environment for construction materials in the reactor. Severe corrosion and high wear rates of the lining material is a hurdle that has to be overcome to make the process more efficient.

    The objective of this work is to investigate the nature of the destructive interaction between ash forming elements and refractory materials to provide new knowledge necessary for optimal refractory choice in entrained flow gasification of woody biomass. This has been done by studying materials exposed to slags in both controlled laboratory environments and pilot scale trials. Morphology, elemental composition and distribution of refractories and slag were investigated with scanning electron microscopy and energy dispersive X-ray spectroscopy. Crystalline phases were investigated with X-ray diffraction, and thermodynamic equilibrium calculations were done in efforts to explain and make predictions of the interaction between slag and refractory.

    Observations of slag infiltration and formation of new phases in porous materials indicate severe deterioration. The presence of Si in the materials is limiting intrusion by increasing the viscosity of infiltrated slag. This is however only a temporary delay of severe wear considering the large amount of slag that is expected to pass the refractory surface. Zircon (or zirconium) (element or mineral?) based material show promising properties when modeled with thermodynamic equilibrium, but disassembling of sintered material and dissociation of individual grains was seen after exposure to a Si- and Ca-rich slag. Fused cast materials have a minimal slag contact where the only interaction is on the immediate hot face. Dissolution was however observed when exposed to a silicate-based slag, as was the formation of NaAlO2 after contact with black liquor.

  • 104.
    Carleborg, Mattias
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Elanvändning i skolkök2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 105.
    Cederquist, Joel
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Från zinkfosfatering till silanbehandling: Potentiell kostnadsbesparing i förbehandlingen hos Ålö AB2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this thesis is to investigate if cost reductions can be accomplished by changing the pretreatment method from zinc-phosphating to silane at Ålö’s plant in Brännland.

    A survey has been conducted to identify economic benefits and drawbacks of the two techniques. The survey, facilitated by chemical supplier, Chemetall, is in the form of an application for calculation of process and chemical parameters for the current process so that comparative results can be presented for evaluation in the form of prospective savings per annum in the event of a change of pretreatment method.

    The zinc-phosphating technique is a conventional method, utilizing activation and crystallization steps, which, when correctly exercised, facilitates both good corrosion resistance and paint adhesion. Drawbacks of this method include high water and energy consumption, maintenance costs, and the generation of toxic waste that requires human handling and expensive disposal.

    Silane pretreatment is a comparatively new method used by Ålö’s facilities in the USA and China, as well as established international automotive manufacturers. This method of pretreatment has developed the quality and stability aspects considerably, has the advantages of lower water and energy consumption and a non-toxic waste generating process. It is considered capable of fully replacing zinc-phosphating without compromising corrosion resistance or paint adhesion characteristics.

    The most important conclusion from this thesis is that the silane pretreatment method is economically beneficial for Ålö at the current rate of production (21 333 front-loaders per annum), with an estimated cost reduction of 25 % or more than € 50 000 per annum. The results of this report also indicate a rise in economic benefits with silane pretreatment in the event of increased production rates.

    This shows that although the silane pretreatment method entails the possibility of substantial annual cost reduction, further investigation in this field is required.

  • 106.
    Chevalier, M.
    et al.
    FFA, the Aeronautical Research Institute of Sweden.
    Berggren, Martin
    FFA, the Aeronautical Research Institute of Sweden.
    Accuray of Gradient Computations in Aerodynamic Shape Optimization2000In: Paper ICAS 2000-2.4.5, 2000Conference paper (Refereed)
  • 107.
    Chevalier, M.
    et al.
    FOI, Stockholm.
    Högberg, M.
    FOI, Stockholm.
    Berggren, Martin
    Sandia National Laboratories.
    Henningson, D. S.
    Department of Mechanics, KTH, Stockholm.
    Linear and Nonlinear Optimal Control in Spatial Boundary Layers2002In: AIAA 3rd Theoretical Fluid Mechanics Meeting, St. Louis, MO.: AIAA Paper 2002-2755, 2002Conference paper (Refereed)
  • 108.
    Classon, Andreas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Enkelt utbytbara instegs delar: En ny lösning för en instegsmodul till lastbil med högmognadsgrad. Forskning har fokuserats på ergonomi och materialval.2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The task was to deliver a solution that could be implemented in today’s production of the FH truck. To make the project successful it was most important that the end result had a high maturity level. For that reason an analysis of ergonomic, laws and regulations, and possible materials where conducted. To show that this project is profitable and can be realized a ruff cost estimated of material and tools is added to the research. By doing smart material choices and not changing more than necessary existing part or for that matter add more parts the outcome is more economic then if the whole ingress module is change. Catia V.5 is used as a construction program and the built-in FEA module (Finite Element Analysis) to check the strength of the construction. This is done to see that the product withstands the applied force from a person. The project result is a updated version on the ingress module where the footboard is easily change without having to remove any parts of the module. What has happened is that the footstep is divided in to two parts, one frame that’s mounted on the chassi on the truck and one footboard that is mounted on the frame. That meant that the plastic cover hade to be change as well as the footsteps. The assembly line for this new ingress module is almost identical to what it is today besides the footboard that’s added. The weight has been reduced with 15 % without doing any bigger changes on the assembly line or adding cost (if not counting for new tools). 

  • 109.
    Collén, Emil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utvärdering av dämpningsmaterial: Förbättringspotential av ljudtryck vid luft- och strukturburen excitering2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been completed in co-operation with Trelleborg Sealing Solutions Kalmar AB. They specialize in developing laminated damping- and isolation products for breake systems. The assignment was to compare different damping materials when excited with airborne and structure borne excitation and to present a proper result, defining one superior method of damping for each type of excitation. Superiority in this case is damping the total sound pressure level the most. This project does not include analyzing the vibrations, merely the noise they cause. All measurement samples has been done with two microphones in a semi anechoic chamber on an aluminum housing representing an oil sump. The excitations has been produced with a speaker and a shaker. The damping materials included in this project are 5 different methods of damping and isolation, made out of different materials and with varying thickness. The result of the comparison between the methods prove ADF (Applied damping foam) to be the most effective method of lowering the sound pressure level with airborne excitation. With structure borne excitation ADM (Applied damping material) proved to be the most effective. With both types of excitation the laminate “dual wall solution” proved to have the lowest effect.

  • 110.
    Dahlberg, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Underhåll av Ortvikens gasisolerade 130 kV-brytare2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    SCA is experiencing problems with arc-overs inside some of the circuit breakers in their gas insulated 130 kV switchgear at the Ortviken paper mill in Sundsvall. The arc-overs is a result of dust in the breaker chamber. The dust comes from wear, which in turn is a result of that the circuit breakers is operated very frequently in combination with minimal maintenance. When an arc-over occurs there is a production stop at the paper mill and the outcome is associated with great costs. Some maintenance measures is currently being carried out to mitigate the risk of arc-overs, however SCA is interested in other solutions and opportunities.

    This report will examine and present the measures that can be carried out in order to prolong the technical lifetime of the circuit breakers. Relevant information and experience will be collected through interviews and later consolidated and presented as the following three alternative measures;

    1. Audit of the circuit breakers
    2. Rebuilding of the plant
    3. Continued vacuuming

    The preferred option is alternative 1 and 2 combined. Alternative 3 is not preferable but could as a last resort be improved with extended measurements and analysis.

  • 111.
    Dahlin, Jonathan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energikartläggning av Palmsundas industrifastighet, Kolen 3.: Energy audit of Palmsundas industrial property, Kolen 32014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project has been done with the help of TM-konsult AB in Lycksele during the spring of 2014. The course is a concluding moment at 15 hp within the engineering exam, energy technique, at the institution of applied physics and electronics, Umeå University. 

    The aim of this work was to evaluate Palmsundas industrial property, Kolen 3, located on Furuviks industrial area. To perform an energy audit and to come up with energy efficient actions that will lead to a lower energy performance of the building. 

    The work initially started with, by hand calculated the buildings heat energy with the help of A-drawings and design drawings. The method that was used is called degree hours. By making a model in the energy program ViP-Energy which give some sort of backup to the calculations by hand. 

    The inventory of the buildings technical installations has been done by a multiple visits. During the visits there were formed opinions about what actions which could be interesting to examine. The Energy efficient actions that have been examined are: 

    • Assembly of an extra window 

    • Doors and ports 

    • Installations of a new vent system in the older part of the building 

    • Vent systems specific fan power 

    • Redundant windows 

    • Lower the indoor temperature 

    • Radiator system in office staff facilities 

    • The compressed air system  

    • The heat systems circulations pumps 

    • The buildings lightning system 

    The one action that stood out from the rest is to change the entire vent system in the older part of the building. The vent system that’s in the older part of the building are six supply air fans, and also works as a heating system by directly heating the cold outside air. If the inside temperature was lowered by night when no one is present, it was possible to see that a lot of energy was saved. 

    Life cycle assessment has been performed on almost every energy efficient action to determine if the actions are viable or not. 

    To summarize, older industrial properties are in a big need of energy efficiency, even big and small investments are viable in the long haul.

  • 112. De Alcantara Dias, Bruno Martin
    et al.
    Maria Lagana, Armando Antonio
    Justo, Joao Francisco
    Yoshioka, Leopoldo Rideki
    Dias Santos, Max Mauro
    Gu, Zonghua
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Model-based development of an engine control module for a spark ignition engine2018In: IEEE Access, E-ISSN 2169-3536, Vol. 6, p. 53638-53649Article in journal (Refereed)
    Abstract [en]

    A Spark ignition (SI) engine is a complex, multi-domain component of the vehicle powertrain system. The engine control module (ECM) for an SI engine must achieve both high performance and good fuel efficiency. In this paper, we present a model-based development methodology for an open architecture ECM, addressing the entire development lifecycle including a control algorithm design, parameter calibration, hardware/software implementation, and verification/validation of the final system, both with bench tests on a dynamometer and in a real vehicle on the road. The ECM is able to achieve similar performance as the original proprietary ECM provided by the original equipment manufacturer. Its flexible and modular design enables easy extensibility with new control algorithms, and development of new engine types.

  • 113.
    De Spiegeleer, Alexandre
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Hamrin, Maria
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Pitkänen, Timo
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Volwerk, M.
    Mann, Ingrid
    Umeå University, Faculty of Science and Technology, Department of Physics. Department of Physics and Technology, The Arctic University of Norway, Tromsø, Norway.
    Nilsson, H.
    Norqvist, Patrik
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Andersson, L.
    Vaverka, Jakub
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Low-frequency oscillatory flow signatures and high-speed flows in the Earth's magnetotail2017In: Journal of Geophysical Research - Space Physics, ISSN 2169-9380, E-ISSN 2169-9402, Vol. 122, no 7, p. 7042-7056Article in journal (Refereed)
    Abstract [en]

    Using plasma sheet data from Cluster 1 spacecraft from 2001 till 2011, we statistically investigate oscillatory signatures in the plasma bulk flow. These periodic oscillations are compared to high-speed and quiet flows. Periodic oscillations are observed approximately 8% of the time, while high-speed flows and quiet flows are observed around 0.5% and 12% of the time, respectively. We remark that periodic oscillations can roughly occur everywhere for x(gsm) < -10 R-E and |y(gsm)| < 10 RE, while quiet flows mainly occur toward the flanks of this region and toward x = -10 R-E. The relation between the geomagnetic and solar activity and the occurrence of periodic oscillations is investigated and reveal that periodic oscillations occur for most Kp values and solar activity, while quiet flows are more common during low magnetospheric and solar activity. We find that the median oscillation frequency of periodic oscillations is 1.7 mHz and the median duration of the oscillation events is 41 min. We also observe that their associated Poynting vectors show a tendency to be earthward (S-x >= 0). Finally, the distribution of high-speed flows and periodic oscillations as a function of the velocity is investigated and reveals that thresholds lower than 200 km/s should not be used to identify high-speed flows as it could result in misinterpreting a periodic oscillations for a high-speed flow.

  • 114. Decharat, Adit
    et al.
    Yu, Junchun
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Boers, Marc
    Stemme, Göran
    Niklaus, Frank
    Room-temperature sealing of microcavities by cold metal welding2009In: Journal of microelectromechanical systems, ISSN 1057-7157, E-ISSN 1941-0158, Vol. 18, no 6, p. 1318-1325Article in journal (Refereed)
    Abstract [en]

    In this paper, we present a wafer-to-wafer attachment and sealing method for wafer-level manufacturing of micro-cavities using a room-temperature bonding process. The proposed attachment and sealing method is based on plastic deformation and cold welding of overlapping metal rings to create metal-to-metal bonding and sealing. We present the results from experiments using various bonding process parameters and metal sealing ring designs including their impact on the resulting bond quality. The sealing properties against liquids and vapor of different sealing ring structures have been evaluated for glass wafers that are bonded to silicon wafers. In addition, wafer-level vacuum sealing of microcavities was demonstrated when bonding a silicon wafer to another silicon wafer with the proposed room-temperature sealing and bonding technique.

  • 115.
    Demirgok, Berk
    et al.
    Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506, USA.
    Ugarte, Orlando
    Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506, USA.
    Valiev, Damir
    Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, NJ 08544, USA.
    Akkerman, V’yacheslav
    Department of Mechanical and Aerospace Engineering, West Virginia University, Morgantown, WV 26506, USA.
    Effect of thermal expansion on flame propagation in channels with nonslip walls2015In: Proceedings of the Combustion Institute, ISSN 0082-0784, E-ISSN 1878-027X, Vol. 35, no 1, p. 929-936Article in journal (Refereed)
    Abstract [en]

    Propagation of premixed flames in narrow channels is investigated by means of extensive numerical simulations of a complete system of combustion and hydrodynamic equations, incorporating transport properties (thermal conduction, diffusion and viscosity) and Arrhenius chemical kinetics. The system includes mass conservation and Navier–Stokes equations as well as those for the energy and species balance. A flame propagates from the closed end of a channel to the open one. An initially planar flame front gets corrugated due to wall friction and thereby accelerates. It is shown that a flame exhibits an exponential state of acceleration only when the thermal expansion coefficient Θ exceeds a certain critical value Θ>Θc. The quantity Θc is tabulated as a function of the Reynolds number related to the flame propagation, Re, being Θc≈6 for Re=5∼20. The major flame characteristics such as the flame propagation speed and acceleration rate are scrutinized. It is demonstrated that the acceleration promotes with Θ   but weakens with Re. In this respect, the present computational results support the theoretical prediction of Bychkov et al  . Physical Review E 72 (2005) 046307 in a wide range of Θ   and Re. While very good quantitative and qualitative agreement between numerical and theoretical results is found for realistically large thermal expansion, Θ>=8, agreement deteriorates with decreasing Θ. Specifically, while the theory and modeling do not quantitatively agree for Θc<Θ<8, they nevertheless demonstrate a qualitative resemblance (the exponential state of acceleration). Finally, no exponential acceleration at Θ<Θc denotes that the theory completely breaks in that case, but this fits other works in the field and thereby allows reconciling various formulations on the flame acceleration.

  • 116. Deng, Na
    et al.
    He, Guansong
    Gao, Yuan
    Yang, Bin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Zhao, Jun
    He, Shunming
    Tian, Xue
    Comparative analysis of optimal operation strategies for district heating and cooling system based on design and actual load2017In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 205, p. 577-588Article in journal (Refereed)
    Abstract [en]

    Computational load significantly influences energy and cost savings when developing an operation strategy for a district heating and cooling system. In this study, a model was identified to study the effects of the difference between design load and actual load on an optimal operation strategy. The established model is strongly dependent on the economy principle, and the proposed optimal strategy could achieve a dynamic balance between the users' load and the system energy supply. This model was validated at 30% load rate, which demonstrated an obvious cost saving of 63.6% under the actual load and 42.2% under the design load. Based on the current strategy, the optimal strategy at different load rates was analyzed with respect to two characteristics of each subsystem: energy outputs and operation costs. Furthermore, in the optimal strategy, changes in total operation costs and cost savings rates under different load rates are also discussed. The results showed that, when the load rate was changed from 30 to 75%, the savings rates based on the design load were 42.2, 17.9, 2.5, and 12.6%, and the savings rates based on the actual load were 63.6, 49.8, 34.3, and 25.7%, respectively. Based on the actual load, the energy savings advantage of the optimal operation strategy could be maximized, in particular, during the initial stage of project construction. Furthermore, the commercial software MATLAB was used for programming and calculations. The simulation results indicated that the application of the combined cooling, heating, and power system could significantly improve the cost-effectiveness.

  • 117.
    Dion, Claude
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Demirgok, Berk
    Dept. Mechanical and Aerospace Engineering, West Virginia University, 26506 Morgantown, USA.
    Akkerman, Vyacheslav
    Dept. Mechanical and Aerospace Engineering, West Virginia University, 26506 Morgantown, USA.
    Valiev, Damir
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Bychkov, Vitaly
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Acceleration and Extinction of Flames In Channels With Cold Walls2015In: Proceedings of the 25th International Colloquium on the Dynamics of Explosions and Reactive Systems / [ed] M.I. Radulescu, 2015Conference paper (Refereed)
  • 118.
    Dion, Claude
    et al.
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Demirgök, Berk
    Dept. Mechanical and aerospace Engineering, West Virginia University.
    Akkerman, Vyacheslav
    Dept. Mechanical and aerospace Engineering, West Virginia University.
    Valiev, Damir
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Bychkov, Vitaly
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Flames in channels with cold walls: acceleration versus extinction2015In: MCS 9, 2015Conference paper (Refereed)
    Abstract [en]

    The present work considers the problem of premixed flame front acceleration in microchannelswith smooth cold non-slip walls in the context of the deflagration-to-detonationtransition; the flame accelerates from the closed channel end to the open one. Recently, anumber of theoretical and computational papers have demonstrated the possibility of powerfulflame acceleration for micro-channels with adiabatic walls. In contrast to the previous studies,here we investigate the case of flame propagation in channels with isothermal cold walls. Theproblem is solved by using direct numerical simulations of the complete set of the Navier-Stokes combustion equations. We obtain flame extinction for narrow channels due to heat lossto the walls. However, for sufficiently wide channels, flame acceleration is found even for theconditions of cold walls in spite of the heat loss. Specifically, the flame accelerates in thelinear regime in that case. While this acceleration regime is quite different from theexponential acceleration predicted theoretically and obtained computationally for theadiabatic channels, it is consistent with the previous experimental observations, whichinevitably involve thermal losses to the walls. In this particular work, we focus on the effectof the Reynolds number of the flow on the manner of the flame acceleration.

  • 119.
    Dolvander, Linus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Styrsystem till bromsvagn: Avsedd för klimatiska tester av militärfordon2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This degree project is part of a prestudy of a hydraulic brake wagon designed to be towed for endurance testing of military vehicles. This report presents the design of the control system for the brake wagon. It describes the programming of a control system for a hydraulic system developed in parallel, the search of potential component suppliers, and the compilation of a failure analysis. The result was a control system programmed in CODESYS, with an operator interface, a block diagram of the system and a Failure Mode Effect Analysis. The conclusion is that a prototype could be built based on this work but a modification of the system and certain risks should be considered.

  • 120.
    Dyrlind, Johan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Sänkning av fjärrvärmetemperaturen för ökad elverkningsgrad2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Umeå Energi AB provides the majority of Umeå municipality with district heating. In the central district heating system there are two power plants that produce both heat and electricity from waste, Dåva 1, and biofuels in the form of wood chips and peat, Dåva 2.

    Combined Heat and Power (CHP) plants will normally have a better electrical efficiency if district heating supply temperature is lowered; therefore the possibility and profit potential of lowering the supply temperature from the CHP plants and alsothe other heat-producing plants in the network have been investigated.

    The purpose of this thesis has been to investigate the possibility of lowering the supply temperature in Umeå Energi´s district heating network and to calculate the possible income increases if it is done.

    To be able to lower the supply temperature without reducing the heat production, the flow in the district heating network must be increased so that the same amount of heat can be delivered. This thesis examined both the current situation including the current flow constraints and the new constraints that will apply when an additional booster station is plugged into the district heating network.

    A linear fit of the measured values of the flow temperature and the alpha value, the ratio of produced electricity and heat produced, shows that lowering the supply temperature increases the alpha value for both CHP plants according to the equations below:

    α1=0,5834−0,0029∗TF   α2=0,7136−0,0026∗TF

    In addition to the alpha value heat losses from the distribution network also changes with a change in supply temperature.

    A control curve is currently controlling the supply temperature as a function of outdoor temperature, but according to measured values, the control curve is not followed during the majority of the time. This is taken as a further indication that the control curve for the supply temperature should be revised.

    Linked to district heating network is an absorption refrigeration unit that requires a supply temperature of at least 95°C during the summer. When the absorption refrigeration unit is not in operation, the requirement of the flow temperature is 75°C. It should also be investigated how much profit could be made if the absorption chiller did not require a higher supply temperature.

    All calculations have been performed based on measured data from the years 2010 and 2011, data that is considered to be representative also for future years. New control curves have been recommended based on the calculations for optimizing profit with the measured data from the years mentioned above years, calcaulations for the increased income using these control curves have also been done.

    With the current operating condition the potential profit is calculated to be around three million Skr per year with an additional two million in profit if the chiller does not require a higher temperature during the summer.

    With a new booster station the estimated profit differs quite a lot between the years with around 17 million Skr of potential profit in 2010 and 11 million Skr in 2011. The profit if the chiller doesn’t require a higher temperature is basically unchanged, about two million Skr.

    The conclusion of the thesis is that it is both possible and profitable to change control curve and use a lower supply temperature. Since 2010 was a unusually cold year and 2011 was a unusually warm year the calculated profits are considered representative also for coming years. The maximum flow with a new booster station is based entirely on theoretical values and should be considered as more insecure then the other results. It is recommended to try the control curves from this thesis in the production and evaluated the profit in a real situation.

  • 121.
    Edberg, Erik
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Chassi För Bromsvagn: Bromsvagn avsedd för klimatiska tester för fordon2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents my thesis for a Bachelor of Science in Mechanical Engineering at Umeå University. The thesis is part of a pilot study for a brake trailer, that BAE Systems Hägglunds AB have considered using for vehicle testing at their testing department. The pilot study has been done together with three other students, that have worked with integrated parts. Strength of materials, Computer-Aided Design(CAD) and Finite Element Method(FEM) have been the main theory of this report. The implementation describes how the chassis was designed in CAD and how strength analyses were performed by hand and with FEM. A failure modes and effects analysis was made with the purpose of analysing what could go wrong with the design.Quotation of different modelled components have been investigated together with possible suppliers. The calculated effective stress that emerged in a section of the chassis loading platform was compared with the FE-analyses. The difference in stress was not significant and therefore it was deemed within reasonable values. The report concludes with suggestions for continued work.

  • 122.
    Edlund, Jeanette
    et al.
    Sveriges lantbruksuniversitet.
    Servin, Martin
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Keramati, Ehsan
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    A long-tracked bogie design for forestry machines on soft and rough terrain2013In: Journal of terramechanics, ISSN 0022-4898, E-ISSN 1879-1204, Vol. 50, no 2, p. 73-83Article in journal (Refereed)
    Abstract [en]

    A new design for a tracked forestry machine bogie (long track bogie; LTB) on soft and rough terrain is investigated using nonsmooth multibody dynamics simulation. The new bogie has a big wheel that is connected to and aligned with the chassis main axis. A bogie frame is mounted on the wheel axis but left to rotate freely up to a maximum angle and smaller wheels that also rotate freely are mounted on the frame legs with axes plane parallel to the driving wheel. The wheels are covered by a single conventional forestry machine metal track. The new bogie is shown to have higher mobility and cause less ground damage than a conventional tracked bogie but requires larger torque to create the same traction force as a conventional bogie. The new bogie also gives less acceleration when passing obstacles than the conventional bogie. Additionally, due to the shape and size of the new bogie concept, it can pass wider ditches.

  • 123.
    Edlund, Martin
    Umeå University, Faculty of Science and Technology, Umeå Institute of Design.
    Jacques: Your underwater camera companion2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    300 million pictures are uploaded everyday on Facebook alone. We live in a society where photography, filming and self-documentation are a natural part of our lives. But how does it inflict on our experiences when we always are considering camera angles, filters and compositions? We might very well ruin the experiences we so badly want to save.

    Scuba diving is a special experience. We enter a world with another space of movement, surroundings and animal life. An experience that can only be experienced for a limited time. An adventure one want to remember, save and share. But what implications does it have on ones experience if one also have to focus on documenting it?

    JACQUES is a product that enables the diver´s to document their dive as a memory to re-experience later and share with others while still leaving them fully immersed in their diving experience. With relatively simple technology such as sonar and video object recognition Jacques can film the diver´s underwater adventure and adept to their behavior without the diver even noticing it. And by being focused on the actual dive one also becomes a better and safer diver.

  • 124.
    Edström, Oskar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av automatisk monteringscell2013Independent thesis Basic level (professional degree), 180 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport presenterar ett examensarbete som handlar om en konceptstudie för en monteringscell. Examensarbetet har genomförts av Oskar Edström, student inom maskinteknik på Umeå Universitet, under våren 2013.

    Syftet med arbetet har varit att utveckla en lösning för hur en bussning, som används i Volvos lastvagnar, skall monteras ihop automatiskt i en produktionscell. Arbetet har genomförts i samarbete med uppdragsgivaren HT-Svarv i Kalix

    För att definiera befintliga problem med dagens konstruktion har förstudier, med kartläggning av företagets behov, genomförts. HT-Svarv vill ändra hur bussningen monteras ihop. Detta för att få kortare operationstid under processen och minska behovet av personal vid montering. Före automatisering monterades bussningen ihop manuellt.

    Koncept har genererats i en dialog tillsammans med uppdragsgivaren där man diskuterat olika lösningar för konstruktionen. Koncepten har sedan utvärderats och sållats fram. Vid modellering för koncepten har CAD-programmet Solid Works använts.

    Arbetet resulterade i en lösning där monteringscellen är uppbyggd i tre stycken operationer samt med en efterföljande kontrollstation. För vidareutveckling av valt koncept bör fokus ligga på produktionsoptimering och tester av funktionsprototyper.

  • 125.
    Edvardsson, Jonas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nötningsrigg för länksystem i skogsmaskinsband2019Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project has been executed at the forestry machine track manufacturer Olofsfors AB and has been aimed at development of a rig for simulation of the wear that occurs in the linkage of Olofsfors AB forestry machine tracks. The problem is that link hooks in the tracks wears out first, often several times faster than other components. Olofsfors AB want to be able to test this wear in a controlled environment. The purpose of the wear rig is to distinguish what type of wear that is in effect as well as be able to optimize materials for Olofsfors AB: s products.

     

    The project began with an pilot study of different types of relevant wear and different types of complete methods of wear measurement and simulation to better understand the problem. After this a market screening of existing machines and rigs that could be of interest was done. The project continued with creation of concepts of wear rigs and methods of wear. After a selection process the project proceeded with one concept to a 3D prototype.

     

    From the market screening it could be found that the market is very thin with few suppliers. Their products are relatively expensive and need specially made test samples. The recommendation to Olofsfors AB will therefore be to construct a rig themselves. The market screening could be used by Olofsfors AB as a basis if they decide to expand their test activity in the future. 

     

    The project reached the overall goals and delivered a prototype that passes the set demands. This means that the project is basically ready to move on to construction of a physical wear rig. There are still some problems to overcome but these will be easiest to solve during the construction phase. 

  • 126.
    Egelstig, Martin
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktiv utformning av vikplog2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This project is about investigation and improvement of a V-plow for the company Swekip. A V- plow is used for snow removal but this product has been found to have deficiencies in its construction, breaking down and not living up to the desired objectives. This is because the product is ordered from a company in China where they have some problems with understanding the purpose of the plow.

    Initially the existing plow is investigated, all the shortcomings set out and examined, what is wrong and what needs improvement?

    When the solutions were done they were evaluated and examined that they actually live up to the desired requirements.

    This assignment is a pure construction project where the majority is implemented in CAD, where models are developed and FE analyses are carried out. But the project also includes a feasibility study, idea study and hydraulic design.

    The results are presented in the form of a CAD model and associated drawings that will serve as the manufacturing basis for the new V-plow. The finished model is based on the original plow but with many new enhancements to remedy the deficiencies the plow had. 

  • 127.
    Ek, David
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Simulation and Evaluation of Models for a Pre In-Die Cutting and an In-Die Cutting Process2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Pre in-die and in-die cutting are processes coupled to metal forming operations. The aim of the thesis was to find, develop, evaluate and validate simulation models for these processes. The goal for pre in-die cutting model was to split a shell segment into multiple segments and for the in-die cutting model to predict cutting tool forces. All models were also supposed to produce physically correct animations. The simulations were made in LS-DYNA and prepared and analyzed in the pre/postprocessor, LS-PrePost. Three simulation models were developed for pre in-die cutting. All with the possibility to split a metal sheet into multiple parts and produce animations of the results. Two models were developed for in-die cutting, the first model uses only shell elements, whereas the other also uses solid elements to represent the metal sheet. The segments essential for the models functionality and how to use them are described in the thesis. Parameter studies were also performed to the evaluate the effects of different variables in the solid model. It was found that many parameters affect the contact stability, dynamic behaviour and cutting tool forces. The information from these studies was used to find an optimal parameter set that was used to correlate the model to experiments. The model was then able to produce results with good correlation to current experiments and to produce physically correct animations. However the experimental data is limited and further experiments need to be carried out to validate the model for more general cases. Finally a method to connect the in-die cutting model to current forming simulations was developed, described and demonstrated.

  • 128.
    Ek, Karl
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kalkylmodell för dimensionering av bandtransportörer2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis is the result of a final work for a Bachelor Degree in Mechanical Engineering at Umeå University. The project is made for the Swedish mining company Luossavaara-Kiirunavaara Aktiebolag (LKAB). The purpose of the project has been to develop a calculation model that can be used for designing new conveyor belt systems or optimize already installed objects. The program chosen for the calculation model is Microsoft Office Excel. The goal is that the calculation model will minimize the need to hire external workforce in questions concerning conveyor belts.The prioritized variables the calculation model is supposed to be able to handle are mass flow, volume flow, motor power, belt tensions and transition curves. Other variables that can be implemented if time permits are the selection of belt, pulleys, shafts and bearings for the calculated conveyor belt system.During the project the calculation model will be tested against already installed conveyor belt systems. The field studies are supposed to show how accurate the calculated values are compared to the actual ones.The result of the project is a calculation model based on three different calculation books and two manuals from LKAB. The model contains over fifty equations that are calculated immediately after the right variable is inserted into the program. In the fields next to the calculated value, the user can find information about the variable and a reference to the book that the equation is picked up from. The program has preinstalled values for idlers masses and belt weight, however the user can chose to activate the manual function and thus enter other values. The purpose is to leave the program open so the calculation can be based on any manufacturer of belt and idlers. The model is able to handle mass flow, volume flow, motor power, belt tensions, transition curves, belt type based on belt strength, and size on counterweight.Four conveyor belt systems were analyzed during the field study. The technical drawing was used to compare the installed motor power and the required motor power based on the calculations. In all cases, the calculated value was more than 70 % of the installed motor power, which is the minimum relation between the two values according to LKAB standards.During the field study the instantaneous mass flow and corresponding power consumption were analyzed. Thereafter, the mass flow was inserted into the calculation model and the calculated motor power was compared to the measured motor power. The best result gave a margin error of 2 % and the worst result deviated by 22.8 %. No further analyzis regarding the result has been employed. The field study has showed that the measured mass flow was relatively low compared to the value on the technical drawing, meaning that a large amount of capacity is unused. A suggestion for a future study is to investigate if this is a common phenomenon in LKAB and if there is any sustainable solution to optimize the process.

  • 129.
    Ekenbäck, Andreas
    Institutet för rymdfysik (IRF).
    Numerical modelling of ENAs from stellar wind interactions2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Energetic neutral atoms (ENAs) are produced whenever a stellar wind encounters a neutral atmosphere. If a stellar wind proton comes sufficiently close to a neutral a charge-exchange reaction may take place, transforming the proton into an ENA. Unaffected by magnetic and electric fields, ENAs provide an opportunity for global imaging of stellar wind interactions.

    This thesis presents methods and results of numerical modelling of stellar wind interactions. In particular it treats in depth production of ENAs at comets, Mars and the extrasolar planet HD 209458b.

    Sufficiently accurate numerical models of stellar wind interactions require extensive computations. Parallel computing has therefore been used throughout the work, both for fluid and particle simulations of space plasmas. This thesis describes the use of a general simulation tool, providing parallel computing for space plasma simulations.

    The thesis presents estimations of the magnitude and morphology of the ENA production at comets and HD 209458b. It compares the results obtained with observations and analyzes them in the light of ENA production at similar objects. Also, simulated ENA images for Mars were produced and compared to observations.

  • 130.
    Ekevärn, David
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energikartläggning av Martinsons Trä AB2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This is a report of a master thesis in energy technology and has been done by mapping energy usage of the company Martinsons Trä AB. Furthermore, this thesis is a part of NV Eko. The purpose of the report is to give a wider image of how energy is used at Martinsons sawmill in Bygdsiljum by mapping specifically and especially the use of electricity in this case. Certain priorities were made, from a production view, and parts of the factory were mapped.

    Measurements were made in order to map the usage of electricity, data has been collected and interviews were conducted.

    The results of this work are statistics over the mapped factories due to the usage of electricity in the these, together with a number of suggestions of improvements. Such suggestions were that some machines need an oversight or replacing.

    The use of electricity in the factories handling the raw material saw processing was calculated to be approximately 30 % of the electricity bought yearly. The factories concerned with the refining process use a corresponding 18 % and the drying facility uses 40 % of the totalt electricity yearly. It was also calculated that in total, Martinsons sawmill in Bygdsiljum uses 23 Gwh.

    The investment of a new moisturising system in the second refining factory (4 in total) needs to be looked into. An oversight of the one of the saw processing factories transformer is needed and the feeding of electricity to the second refining factory needs to be separated from said transformer. Above mentioned measurement needs to be done with transformer 11 as well, separating the second from the third refining factory:s feeding.

    Furthermore an oversight and replacing of certain machines within the refining factories is needed and also a more continuous logging of electricity usage should be implemented.

  • 131.
    Ekman, Joakim
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energianalys av Romar fastigheter med metodutveckling för ökade incitament för   energieffektivisering hos hyresgäster2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Thesis is to work out an examplel of incentivesto motivate tenants to participate and invest in energy efficiency. The workincludes an energy audit of a building to be able to show what kind of savingsthat can be made and the investment costs involved. The property has all theenergy costs embedde in the price which means that tenants do not haveincentives to invest. The energy audit include night patrols to see what wasteenergy att night when there are no working, collection of data from Umeå Energy,an inventory of lighting and the acquisition of information on ventilation andthe compressor. Contact with different companies to get the approximate cost ofthe rationalizations. After the initial work was done the results were compiledand the result was a reduction in electricity consumtion by 354 MWh/year to 211MWh/year. The incentive in this case involves an adjustment of the rental formso that tenants self-pay energy costs and thus become more interested in beinginvolved in investments. An individual measurement of energy consumtion shouldbe as it is possible to assess how much each tenant is using. Investment costscan be split between tenants and landlords and bebefits of the investments canbe divided in the same way. Both parts benefits econonomically andenviromentally on cooperation.

  • 132.
    Ekström, Evelina
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Evaluation and optimization of PolyCor - a single-use Coriolis flowmeter2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the pharmaceutical industry it has become common to use single-use components in the production line to save time and money. Therefore, a team at General Electric started to develop a single-use Coriolis flowmeter, PolyCor M13, targeted at liquid chromatography systems. A Coriolis flowmeter in this embodiment is simply a tube put into vibration at its natural frequency. When there is a flow through the vibrating tube the Coriolis force arises, causing a phase shift of the pickup signals on each side of the actuator. This phase shift is linearly proportional to the mass flow through the tube.

     The approach of PolyCor M13 is a separate oscillator and flow path. The oscillator is a metal skeleton holding the flow path, a silicone tube. The initial requirement flow range was 0.16-7.8 kg/min with an error less than 2%. Initial tests indicated that the prototype fulfilled these requirements at ambient temperature. This thesis is a further evaluation of the performance of M13. The main goal was to establish the pressure and temperature dependence and find an model to compensate for these. Investigation if M13 can manage flows up to 10 kg/min was also a part of this scope.

     Control measurements showed that flows less than 2 kg/min could give large errors, over 5%. Flows higher than 2 kg/min up to 10 kg/min had errors less than 5%. The error was determined using a reference mass flow. By increasing the pressure in the system, from 0 to 4 bar, the error increased substantially. For the two lowest flows tested, 0.5 and 1 kg/min, the computed mass flows gave errors over 100%. The error for 2 kg/min was around 70% and the error successively decreased for higher flows and at 6-10 kg/min the error was around 20%. A compensation model was established by fitting a polynomial to the data. The best compensation model managed to reduce the error on new test data to 5-10% for flows between 2-10 kg/min. For smaller flows the error was still high but less than 100%.

     Significant deviation from the temperature at which the proportionality was determined caused large errors. Errors for low flows, 0.5 and 1 kg/min, gave errors mainly up to around 50% but some errors were over 100%. For higher flows, 2-10 kg/min the error is up to 30% with some occasional errors up to 60%. The procedure to establish a compensation model for temperature was similar to that for the pressure compensation model. The best model for temperature compensation managed to reduce the error to 5-10% for flows between 2-10 kg/min. For lower flows the error was still high but slightly better, some error was still over 100%.

     In conclusion, M13 is not as reliable as initial tests showed. The error limit is exceeded, especially for flows less than 2 kg/min. A more suitable range would be 2-10 kg/min. The pressure and temperature effects have an enormous impact but can be compensated to some extent. Since the accuracy of M13 is not perfect, errors less than 5% can be difficult to obtain in the current state of M13.

  • 133.
    Emilia, Stjern
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konsekvenser av ett omfattande elavbrott inom äldrevården2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A long term large-scale power outage would have a big impact on the society, not least for the elderly and sick people. The Swedish hospitals are well prepared for a power outage. How the municipal healthcare chain would cope with a large-scale power outage is not as well investigated.

    The purpose with this report is to increase the knowledge about what consequences a power outage would cause at the elderly care homes and how they could prepare for a scenario like that. The goal is to produce a report to ease the planning of emergency power solutions to the elderly care homes.

    To re-establish the power supply in case of a power outage the most common solution today is a diesel generator. An elderly care home was chosen as a reference to be able to calculate how big efficiency that is needed to supply necessary equipment with enough power. The result showed that the diesel generator need to be able to deliver 640 kVA. A model of the elderly care home was built in the simulation software IDA ICE. A simulation was made to decide how fast the temperature inside the building is sinking in case of an interruption in the district heating system. According to the result the temperature inside the building would be 11 ºC after 48 hours with an outside temperature at almost – 20 ºC. During a day with high temperatures can the inside temperature rise to 29 ºC.

    A power outage could cause big problems for the elderly care homes if there are no access of diesel generators. A diesel generator which would supply an elderly care home with electricity will consume a big amount of diesel. To facilitate the distribution of diesel in case of an emergency is it important to establish a plan for how much diesel that would be consumed over a day and how to secure the delivery to the most important places. 

    If the power outage occurs during a period with unusually hot or cold weather the vulnerability increases because the elderly people appear to be more sensitive of overheating or hypothermia. To know which buildings that would be prioritized in case of an interruption in the district heating system ore cooling system, would it be an advantage to document the buildings time constants.

     

  • 134. Enestam, Sonja
    et al.
    Mäkelä, Kari
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Hupa, Miko
    Occurrence of Zinc and Lead in Aerosols and Deposits in the Fluidized-Bed Combustion of Recovered Waste Wood. Part 2: Thermodynamic Considerations2011In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 25, no 4, p. 1970-1977Article in journal (Refereed)
    Abstract [en]

    In the present work, which is the second part in a series of two, multi-phase, multi-component equilibrium calculations were used to study the chemistry and deposition behavior of lead and zinc in the combustion of recovered waste wood (RWW). Particular attention was paid to the deposition behavior in different parts of the boiler under varying flue gas and material temperature conditions. In addition, the influence of fuel composition was considered by studying three different fuel compositions. The results from the calculations were compared to experimental results from two measurement campaigns, whose goal was to experimentally determine the distribution and speciation of zinc and lead compounds in aerosol particles and deposits in the fluidized-bed combustion of RWW. The results from the experimental work are presented in part 1 (10.1021/ef101478n) of this work.

  • 135.
    Enevold, Jenny
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Development of light-emitting electrochemical cells for novel applications2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The work intended to make progress towards the objective of fiber-shaped light-emitting electrochemical cells (LECs). LECs comprising a film of poly(3,4-ethylenedioxythiophene): poly (styrenesulphonate) (PEDOT:PSS) cast from aqueous dispersion as the sole transparent anode were produced and characterized. It was shown that it is possible to achieve uniform yellow-green light emission at an efficiency of 0.96 cd/A from such LECs fabricated by spin coating at low rotational speed. Implications of using different cathode metals and varying the order of deposition of the films were studied and shown to have significant influence on device performance. Lastly, a novel fiber-like LEC in a coaxial geometry was produced, which promises bright prospects for new applications due to the flexibility of the used materials.

  • 136.
    Enfros, Filip
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av tiltmekanism: Tiltmekanism för slaga2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 137.
    Engebro, Magnus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Konstruktion av pressfixtur: För sidoplåtar till gripare G40HD2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis was made for Cranab in Vindeln. Cranab manufactures grapples for the mechanized forestry, which are used to collect and move harvested timber. A grapple consists of two main parts, the gripping claws and a cradle. The cradle is made up by several different parts, whereof two side plates, a right and a left side plate. The side plates are cut in a laser cutting process and are then bent in a press machine, before they are welded together. In the present situation the side plates are feed in to the press machine manually, which takes a long time and the risk is that result is not consistent.This work was to develop a design proposal of a press fixture to Cranab. By creating a fixture the pressing step can be performed more quickly and with higher quality to the final product. This contributes to making Cranabs production more efficient and flexible. The fixture has to be adapted to the existing press machine and must be able to handle both side plates.When designing a fixture there are many parameters to consider, the design must be adapted to the existing machinery and meet the set requirements for both quality and work environment. Consultation with the production staff were carried out to take advantage of their practical experiences and opinions. The final design proposal is a clear improvement over the current handling and meets the stated requirements and demands.

  • 138.
    Englund Sandlund, Emil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energibesparingspotential i belysningssystem2014Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
  • 139.
    Eriksson, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Energikartläggning av fastigheten Brage 62012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 140.
    Eriksson, Anton
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    3D-laserskanning och ytors egenskaper: En studie om semi-transparanta ytor, glans och de vanligaste felen vid skanning2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    3D laser scanning is a useful tool in manufacturing and is being used more and more. It can be hard to use the tool without any experience in scanning.

    This projekt investigates some of the common mistakes that are made by a beginners in scanning. It also examines some materials and their properties in scanning.

     

    The work has been done cooperation with Sliperiet at Umeå University through tests and studies on a handheld laserscanner, the HandyScan300 from Creaform.

     

    The project has resultet in a manual to help beginners in 3D-scanning. A comparison between four different semi-transparent plastic materials and their tendencies to be scanned under the surface. An analysis of glossy surfaces during scanning has also been made.

  • 141.
    Eriksson, Emil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Self-Balancing Robot Control System in CODESYS for Raspberry Pi: Design and Construction of a Self-Balancing Robot using PLC-programming tools2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Department of Applied Physics and Electronics at Umeå University offers education and conducts research in the field of automation and robotics. To raise the competence in automation in the CODESYS development environment it’s proposed to build a remote controlled self-balancing robot as a testing platform which is then programmed using CODESYS for Raspberry Pi.

     

    The chassis of the robot consists of laser-cut plexiglass plates, stacked on top of each other and fixed using threaded rods, nuts and washers. On these plates the robots’ electrical components, wheels and motors are attached.

     

    The control system is designed as a feedback loop where the robots’ angle relative to the gravity vector is the controlled variable. A PID-controller is used as the system controller and a Kalman Filter is used to filter the input signals from the IMU board using input from both the accelerometer and the gyro.

     

    The control system is implemented in CODESYS as a Function Block Diagram (FBD) using both pre-made, standard function blocks and customized function blocks. By using the in-built web-visualization tool the robot can be remote controlled via Wi-Fi.

     

    After tuning the Kalman Filter through plot-analysis and the PID-controller through Ziegler-Nichols method the robot can stay balanced on a flat surface.

     

    The robots’ performance is tested through a series of test scenarios of which it only completes one out of four. The project ran out of time before further testing could be done.

     

    For future work one could improve the performance of the PID-controller through more sophisticated tuning methods. One can also add a steering-function or test different type of controllers.

  • 142.
    Eriksson, Joakim
    Umeå University, Faculty of Science and Technology, Department of Physics.
    Simulering av oljeflödet i Scanias växellådor2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    At Scania they want to shorten the development time on their products in order to continue being one of the top manufacturers of trucks in the world. To do this they have find new ways and new tools to increase the knowledge and speed up the development of new products. The oil flow in the gearbox is such an area in which they have examined the possibilities to increase the knowledge with the aid of computer simulations.

    In this thesis work a model for computer simulations of the oil flow through the shafts of the gearbox has been developed in GT-Suite, a module based simulation program in 1D. The model can simulate the flow of oil from the oil pump in the front of the gearbox, all the way back to the sun wheel in the planetary gear and in between the flow to bearings and synchronizers. The aim is to be able to use the model during further development of todays gearboxes and in the future development of new gearboxes.

    The simulations have been validated against measurements which have been performed in which the oil flow to the sun wheel have been measured for various speeds an configurations of the gearbox. The simulations have been able to replicate the measurements in many ways adequately. GT-Suite is well suited for simulations and to use as a reference when making adjustments to the gearbox and in the future when developing new gearboxes. The result from simulations in GT-Suite have also been validate against CFD-simulations in 3D for some specific components. The advantage of CFD-simulations is that more knowledge of the flow can be obtained even for complicated geometries. The disadvantage is that the complexity when simulating the entire system makes it almost impossible, so mostly subsystems must be studied.

    In the future more work in form of new measurements and simulations in CFD-programs will be necessary to further improve the model. But already now the results of simulations have been able to increase the knowledge of the oil flow in the gearbox. And this in turn have helped designers to solve some challenges they have had, but also discovered new ones that could be solved by simulations and examine what changes are required. 

  • 143.
    Eriksson, Magnus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Avvibrering av drivenhetsupphängning CV90: En studie gjord på BAE systems i Örnsköldsvik2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The noise level on CV90 has always been a big problem, loud noise and great vibrations have been a part of everyday work for the crew. BAE-systems are the developerOf CV90 have started a work with the goal to lower the noise and vibrations in the vehicle. Tests have been made witch shows that the biggest source of the problem is the track. A new track has been constructed, in rubber instead of the traditional steel track. Tests witch have been made on the rubber track shows that nest source of vibrations and noise is the engine and transmission suspension, today the transmission is mutely mounted on the body.The new suspension has been modified from the present, but it has been made bigger so a rubber damper can be fitted between the transmission and the holder. When the rubber damps 1cm it will absorb the force of 2.5G, meanwhile it must hold the force of 5G in every direction. The forces have been simulated by FEM-analysis.A new construction have been made witch fore fill the demands on forces. The natural frequency on the rubber has been calculated to 9.83 Hz, which is around 3 times less the frequency on the engine when the engine is idling(33.33Hz). The idling frequency on the engine is the lowest frequency that will affect the dampers. The transmission will have full damping effect on idling, when the speed raises will the track be the biggest source of vibrations and noise. But on idle this problem will be considerably lowered.

  • 144.
    Eriksson, Magnus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    TENSEGRITET: Flexibla strukturer med många användningsområden2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Sliperiet is located in Umeå and runs an interdisciplinary project named +Project. Through this project, they want to investigate an area of flexible structures where the subject of tensegrity is included. A tensegrity structure consists of struts enclosed in a web made up of wires and is held together by a combination of compressions and stresses. There exists a ratio between the length of the struts and the length of the wire, which affects the properties of the structure. The purpose and goal of this work is thus to produce and investigate tensegrity structures, with the intention of launching the subject of tensegrity within the field of flexible structures as a part of the +Project. The work is limited to basic tensegrity structures. Three different kind of prototypes and two models are constructed based on basic tensegrity structures. The manufacturing of a third model started but was cancelled to keep the time frame for the project. Most of the goals were met and improvements that could be made in the production of the models are presented, as well as proposals for future work.

  • 145.
    Eriksson, Marcus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Produktionsunderlag för fixtur till BioProcessramar2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis is made on behalf of General Electric Healthcare Bio-Sciences AB in Umea. GE Healthcare is a company that produces health care products. One of these products is BioProcess which is used in medical research and the manufacturing of pharmaceuticals. The product often have to be modified since itis soldcustomer modified. There are two different frame sizes. The frames are often tilted 90 degrees to make the modification areas easier to access. The modifications made is mostly trace grooves and holes.The project goal was to create a fixture that fits both frames and will make the modifications made to the frames easier. The fixture should reduce the bodily wear that is caused by modifying these frames. The structure of the fixture must meet requirements of functionality and safety.The result of the project is a fixture that is compatible with both frame sizes. The fixture has been dimensioned with a safety factor of 4. This safety factor was chosen because of the risks in the operations.

  • 146.
    Eriksson, Matias
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Hökfors, Bodil
    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.
    The Effects of Oxygen Enrichment and Fuel Composition on Rotary Kiln Lime Production2015In: Journal of Engineering Technology, ISSN 0747-9664, Vol. 32, no 1, p. 30-43Article in journal (Refereed)
    Abstract [en]

    This article discusses the impact of oxygen (O2) enrichment on rotary kiln lump lime production. A predictive simulation tool is utilized to investigate the effect of O2 enrichment on the following key parameters of the lime process: kiln temperature profile, product quality, specific energy consumption and kiln production capacity. Three fuel mixes - 100% coal, 90% coal and 10% waste derived fuel oil, and 90% coal and 10% sawdust - are simulated at three oxygen levels. The oxygen levels represent three scenarios: no enrichment (21% O2), moderate enrichment (23% O2), and moderate-to-high enrichment (25% O2). This work is a part of the on-going efforts to reduce the environmental impact of industrial production. Reducing emissions, utilizing biofuels and waste derived fuels, full utilization of raw materials, and energy efficiency are areas of importance for industry. In the long term, oxyfuel technology, i.e., combustion with recirculated kiln gases and pure oxygen, could allow for near-zero emission production and carbon sequestration from industry and power production. In the short term, emission reductions in lime production must be achieved through other means, such as energy efficiency. As a step on the path to a near-zero emission lime plant, this paper describes an investigation of the influence of oxygen enrichment in rotary kiln lime production. The simulated results show positive effects of O2 enrichment, and the simulation results have been used by the kiln operator for in-house training. Results indicate that oxygen enrichment applied to lime production can reduce energy consumption and emissions.

  • 147.
    Eriksson, Morgan
    et al.
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Golriz, M. R.
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Radiative Heat Transfer in Circulating Fluidized Beds2005In: International journal of thermal sciences, ISSN 1290-0729, E-ISSN 1778-4166, Vol. 44, p. 399-409Article in journal (Refereed)
    Abstract [en]

     

    A new model for predicting radiation heat transfer in circulating fluidized bed combustors is proposed. The model assumes two phase structure, the flow at the wall dominated by streamers of clusters traveling mostly downward, interspersed with periods where there is upwards flow of a dilute suspension. Also, the model assumes the intensity distribution to be semi-isotropic in the forward and backward direction. The predictions are in good agreement with the experimental results from the literature. Finally, a parametric study is performed to show the effect of different bed parameters on radiative heat transfer. The results indicate that suspension temperature, wall temperature, wall emissivity, particle emissivity, and suspension density have significant influence on the radiation heat transfer coefficient.

     

  • 148.
    Eriksson, Per
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Analys av uppvärmningssystem: En kartläggning och analys av uppvärmningssystem för flygplan med fjärrvärme som energikälla.2017Independent thesis Basic level (university diploma), 180 HE creditsStudent thesis
    Abstract [en]

    When passenger aircrafts are parked during the nights they need warming and ventilation to prevent freezing of critical components, ventilate accumulated moisture and to satisfy the comfort for cabin crew and passengers before takeoff. Smart Climate Scandinavian AB has developed and delivered a climate unit which uses district heating as a thermal energy source instead of electricity. This system is a more energy efficient and environmental sustainable alternative.

    The purpose of the thesis was to chart and analyze parts of the heating system, if possible to state improvements to reduce used energy due to warming passenger aircrafts. The new heating system was compared to the previous one to see which one was more energy efficient.

    To be able to compare the two systems measurements about temperatures and flow has been collected from the control and regulation system. The measurements have been compiled, evaluated and analyzed with focus not to compromise the probability to not affect the energy- and power calculations. Some of the measurements are provided and collected by the energy meter Kamstrup MULTICAL 602 which has good accuracy and precision, these where used as a reference to rate the measurements from other parts of the system.

    Charting of the system proved that the ventilation ducts where equipped with different thickness off insulation. The results of the power calculations proved that if the heating system used ventilation ducts with an insulation thickness of 20 mm instead of 2 mm requires 16 % less power usage.

    From the analysis of energy calculations, a linear equation which calculate the energy use dependent on outside temperature was determined.

    The results of using the new heating system instead of the previous saves 9200 kWh energy per year and pound. That the new system is more energy effective considers to be likely because its uses regulation of the demand by inside temperature of the aircraft, previous system only used regulation dependent of outside temperature.

    The conclusions of this project are:

    • The sizing of the system is good enough to deliver the required demand.
    • Adjust the active time for preheating.
    • Night time reduction results in marginally less energy use.
    • Use ventilation ducts with insulation thickness of 20 mm.
    • The new heating system is more energy efficient compared to previous.
    The full text will be freely available from 2020-06-01 00:00
  • 149.
    Eriksson, Simon
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Spillvärme för SSAB EMEA Luleå: En utredning av koksverkets förutsättningar att utnyttja spillvärme i det befintliga värmesystemet2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Rising energy prices and better environmental awareness are two reasons that make waste heat utilization increasingly relevant. In Sweden, we have a leading position when it comes to use of waste heat, which amounts to 4 TWh. An investigation by the Swedish District Heating Association, in cooperation with Statistics Sweden shows that there is an unused waste heat potential of 10 TWh. The problems of utilizing waste heat are caused by everything from high investment costs to problems with concluding agreements with district heating companies that benefit both parties.This thesis presents the opportunities for SSAB coke plant to integrate waste heat into the existing heating system and thereby reducing the energy costs.The reports aim is to find out what temperatures and flows that occur in the heating system and optimize it to the appropriate level for heat exchange with waste heat. The goal is also to propose a suitable way of linking the two systems and ensure their mutual functions are not affected.The annual consumption of the coke plant heating system amounts to 16 GWh. Temperature difference over the heat exchanger shows a poor heat exchange in the system, which is mainly caused by unregulated equipment and an oversized pump. Proposed measures with payback periods shorter than one year are presented in the report. Economic conditions for integrating waste heat are also favorable and turned out to be completely dependent on the amount of heat exchange that can be achieved in the heating system.

  • 150.
    Eriksson Stephanopoulos, Antonios
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Komfortkylsystems installationskostnader och energiförbrukning i kontor2011Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    On behalf of Creanova AB this master thesis has been implemented in the autumn 2010. The aim with the project was to analyze how installation and energy costs for comfort cooling in office buildings depends on different design conditions. The conditions that have been examined is particularly the design indoor temperature, but also sun protection in terms of louvers and blinds as well as LED lighting.

    All the varied parameters have been simulated in four different directions with both CAV (Constant Air Volume) systems with conventional baffle and VAV (Variable Air Volume) systems with active diffuser TTD-160 from Lindinvent.

    The calculations for the office have been simulated in climate simulation program IDA ICE 4.0. After that two different solutions were developed for the office, one with CAV ventilation and one with VAV ventilation. Finally installation cost of each simulation and its energy consumption was calculated.

    The calculations show that the installation costs for an office space will increase by about 50% when the design indoor temperature is lowered from 26 to 22 ° C for the CAV system with supply air baffle. The corresponding figure for the VAV system with inlet diffuser is about 40%. Energy costs for air conditioning and heating will increase by about 114% for the CAV system and approximately 127% for VAV solution in which the same design temperature drop is implemented.

    By attaching different types of sunscreen on the office window, the need for comfort cooling for offices with south, east, or west facade is greatly reduced, which is clearly reflected in the costs for both installation and energy. To attach sunscreen on offices with north facades are not necessary, because the solar radiation on north facades is already very low. The installation costs for the VAV solution has proven to be about 10-15% lower than the CAV solution with the same conditions and energy costs for the VAV solution is between 20-27% lower than for the CAV solution

    But designing VAV systems are not always appropriate, since the ducts and installations take up more space because of the ventilation ducts increased size. When very exclusive buildings are constructed the ventilation ducts increased shaft area may lead to that the lost rental income is greater than the savings that the lower energy consumption generates.

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