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  • 201.
    Blomberg, Camilla
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Wordpress som CMS för mindre webbplatser2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Alla som studerar till Medieproducent på Umeå Universitet ska i slutet av utbildningen genomföra ett examensarbete. Syftet är att visa de kunskaper som utbildningen givit och i samma veva inhämta nya. Detta examensarbete är utfört på beställning av byggföretaget Gottfridsson o Persson Construction AB. Målet var att ta fram en enkel webbplats som skulle vara lätt att underhålla och inbringa nya kunder till företaget. Rapporten tar i första delen upp bakgrunden till detta projekt, dess syfte, förutsättningar det haft samt avgränsningar som gjorts. I den andra delen redogörs bland annat teoretiska delar kring hur en webbplats skapas med Wordpress, vilka för- och nackdelar som finns och ett antal viktiga punkter att tänka på. Den tredje delen  av rapporten beskriver hur arbetet gått till och vilka metoder som användts. Slutligen redovisas resultatet och en diskussion kring hur arbetet gått, samt slutsatser som dragits.

  • 202.
    Blomberg, Hans
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Korta instruktionsvideor inom matlagning2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract  

    This  report  describes  the  production  of  a  number  of  short  instructional  videos  in  cooking.  The  project  was  a  thesis  project  for  Högskoleprogrammet  till  medieproducent,  which  is  a  two-­‐year  program  for  media  production  at  Umeå  University.  

    Video  production  took  place  at  the  request  of  SVT  (Swedish  television)  in  Umeå.  The  videos  are  meant  to  be  used  on  the  cooking  portal  SVT  plans  to  launch  in  the  fall  of  2015.  A  chef  was  hired  to  carry  out  the  procedures  to  be  filmed,  and  the  student  was  assigned  to  shoot  and  edit  everything.  

    Before  production  started,  cooking  instructionals  on  Youtube  were  analyzed,  to  create  an  idea  of  how  such  videos  typically  look  today.  The  results  of  this  analysis  were  then  used  in  the  production,  but  they  were  not  governing  in  the  design,  since  specific  requests  from  others  involved,  and  specific  conditions  of  the  project  existed.  Also  the  student's  own  visions  influenced  the  outcome.  Another  preparation  was  to  set  up  various  options  for  the  design  and  assessing  what  these  different  options  would  mean  for  the  result.  

    Shooting  took  place  in  the  chef's  kitchen,  during  three  days.  Each  video  was  filmed  from  two  angles,  to  facilitate  cutting  therebetween.  The  material  was  edited  with  the  aim  to  convey  both  clarity  and  good  aesthetics.    

    The  experience  resulted  in  recommendations  for  further  work,  in  the  form  of  a  manual  of  how  to  produce  such  cooking  tutorials.  The  manual  describes  what  equipment  is  needed  and  how  to  work  on  set.  Then  the  editing  process,  including  appropriate  lengts  of  the  videos,  is  presented.  The  manual  also  contains  recommendations  for  how  much  time  is  needed  when  producing  a  certain  number  of  short  instructional  videos  of  this  kind. 

  • 203.
    Blomdahl, Pontus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utmattningsprovning av kamringar: Framtagning av testutrustning för utmattningsprovning av kamringar2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Bosch Rexroth in Mellansel develops and fabricates Hägglunds hydraulic motors among other things. One important component of the motor is the cam ring, which commonly affects the life span of the motor. The aim is to create the basis of a testing equipment where a loose cam ring can be tested. Previously, a complete motor has been used in order to test the fatigue resistance of the cam ring. In order to load the cam ring similar to the real case. FEM-analysis was performed to investigate how the cam ring is affected during loading and how the rig should be built for the strains to be similar to the real case. The result of this simulation was compiled in a Haighdiagram in order to get an indication of the magnitude of the stresses. The solution is a testing equipment which consist of a cylinder block which usually is in the motor. The cylinder block is bolted onto a bottom plate where the cam ring has a given position. The cam ring is fixated using a sloted spring pin and a dowel pin that keeps the cam ring in position and prevents potential torque. All pistons should be pressurised by pulsation at the same time using the same pressure, thus, the torque is expected to be zero. One of the holes which is holding the cam ring is oval, this is to allow deformation of the cam ring. The result of this work is a basic plan for the components included which affects the mechanical function of the testing equipment. A limitation of this work has been that the residual stresses in the clearance holes is unknown. These residual stresses have a great importance for fatigue resistance of the cam rings. As a consequence of this, it has been difficult to estimate which working pressure the test rig has to use in order to achieve the desired life span. Experimental testing when using the rig will indicate this. Task monotoring  The testing equipment will generate 1-10 million loading cycles before failure of the cam ring occurs. Will be achieved through experimental testing  Testing time should be reasonable, result would preferably be achieved within 2-4 weeks. Will be achieved through experimental testing  The testing equipment should be customised for a CA 50-50 cam ring. (CA 50 motor series strongest motor 50 Nm/bar) Achieved  Testing equipment should be usable with the current laboratory equipment of Bosh Rexroths (420 bars maximum preassure). Probably achieved  The crack needs to be detected in an appropriate way, to stop the testing. Achieved  The testing equipment needs to be able to be manufactured by using the developed blueprints. Achieved

  • 204.
    Blomqvist, Benjamin
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Rönntoft, Britta
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Jet flow simulations of Baihetan hydropower station’s discharge surface spillways2015Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This project was performed in order to determine if numerical simulations can be used to predict the spreading of a water jet that exits the discharge surface spillways of Baihetan hydropower station. If the spreading ranges can be predicted correctly using numerical simulations, the pressure distribution in the plunge pool downstream the dam can be determined. By being able to determine the pressure distribution, the spillways’ design can then be modified in order to optimize the pressure distribution and thereby minimize the damage on the plunge pool’s river bed. If the spreading ranges can be predicted correctly using numerical simulations it means that numerical simulations can be used as a tool to design future hydropower stations’ discharge surface spillways as a substitute to scale models which are commonly used to optimize the spillway design today.

    A simulation model of Baihetan Hydropower station’s discharge surface spillways was constructed. The model was constructed as two separate parts using the pre-processing software Gambit and then imported to the computational fluid dynamics software Fluent for numerical simulation of the water flow. The numerical simulations were performed with a transient flow, the k-ε turbulence model and the Volume of Fluid multiphase model. The models were simulated with a water level in the dam corresponding to when a massive flood has occurred which happens approximately once every hundred years. The results from the numerical simulation were then analyzed with the post-processing software Tecplot 360. Results in form of water spreading ranges when the jet stream hits the plunge pool were obtained from the numerical simulation and compared to data from an earlier performed experimental study where a scale model was used. The water spreading ranges were measured using a water volume fraction of 0-5 percent. The comparison was done to be able to determine if the results from the numerical simulations were accurate enough so that numerical simulations could be used as a substitute to expensive scale models when designing hydropower stations’ discharge surface spillways. A sensitivity analysis was performed where different mesh sizes were used and the Fluent setting double precision mode.

    The numerical results were acceptable when checking for convergence, meaning that the equations involved in the simulations were solved properly. The relative difference in water spreading range in the direction of the flow for the Medium mesh size was below 20 percent and thereby considered acceptable while the relative difference in water spreading range perpendicular to the flow was 60 percent for the Medium mesh size and thereby far from acceptable. Possible reasons for these deviations from the experimental results are the approximated uniform velocity profile at the inlet of the spillway and the used k-ε turbulence model. Considering the results obtained in this project, without more detailed study, the numerical simulations using k-ε turbulence model are not advised as a substitute for the experimental methods to determine water flow out of the discharge spill ways of hydropower plants. With more information about the conditions at the inlet and the use of a different turbulence model more accurate results may be obtained. 

  • 205. Bobtsov, A. A.
    et al.
    Nikolaev, N. A.
    Slita, O. V.
    Borgul, A. S.
    Aranovskiy, Stanislav
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    The new algorithm of sinusoidal signal frequency estimation2013In: Adaptation and Learning in Control and Signal Processing, 2013, no PART, p. 182-186Conference paper (Refereed)
    Abstract [en]

    In this paper we consider the new estimation algorithm of the measured sinusoidal signal frequency. Unlike most of known similar methods, the proposed algorithm provides the opportunity of partial rejection of unaccounted disturbances presenting in the channel of useful signal measurement. The latter in its turn allows obtaining more accurate estimation of unknown frequency of the measured sinusoidal signal.

  • 206.
    Bohman, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Single Sign On med Azure AD Connect2016Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report covers Azure AD Connect and Single/Simplified Sign On. Users and customers today places greater demand for easier login method and seamless experience for reaching all services. Microsoft has recently released Azure AD Connect tool to help synchronize passwords between Active Directory and the cloud services Office 365/Azure and 1000s of Software as a service applications. Team Norr IT-partner is an IT company that focuses on delivering Microsoft products to thier customers and therefore wanted to know more about Azure AD Connect. How to configure the solution and what the set requirements are.

    Single Sign On means that you only need to sign in with password and login once and automatically get access the applications that support the technology without any more credentials.  By using a Federated domain users get the best and safest experience with Single Sign On. Simplified Sign On lets users use the same username and password to login with to all applications with support, but no automatic login.

    Azure AD Connect tool installs the roles that are needed to run a Single Sign On or Simplified Sign On. By default the synchronization engine will keep track of information about the users and groups. Passwords are also synchronized between on-premises Active Directory and Azure Active Directory or federation server.

    What the Synchronization engine takes is determined by the rules defined. Password Sync does not install any extra server roles. With the Federation path there will be extra roles installed called Federation (AD FS) and Web Application Proxy (WAP). They handle the authentication of users instead of the normal Microsoft authentication. There is some set requirement for the servers that host the roles depending on the size of Active Directory and numbers of users. The servers need a certain base performance for it to work properly. 

  • 207. Bolling, Anette Kocbach
    et al.
    Pagels, Joakim
    Yttri, Karl Espen
    Barregard, Lars
    Sallsten, Gerd
    Schwarze, Per E
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Health effects of residential wood smoke particles: the importance of combustion conditions and physicochemical particle properties2009In: Particle and Fibre Toxicology, ISSN 1743-8977, E-ISSN 1743-8977, Vol. 6, article id 29Article, review/survey (Refereed)
    Abstract [en]

    Background: Residential wood combustion is now recognized as a major particle source in many developed countries, and the number of studies investigating the negative health effects associated with wood smoke exposure is currently increasing. The combustion appliances in use today provide highly variable combustion conditions resulting in large variations in the physicochemical characteristics of the emitted particles. These differences in physicochemical properties are likely to influence the biological effects induced by the wood smoke particles.

    Outline: The focus of this review is to discuss the present knowledge on physicochemical properties of wood smoke particles from different combustion conditions in relation to wood smoke-induced health effects. In addition, the human wood smoke exposure in developed countries is explored in order to identify the particle characteristics that are relevant for experimental studies of wood smoke-induced health effects. Finally, recent experimental studies regarding wood smoke exposure are discussed with respect to the applied combustion conditions and particle properties.

    Conclusion: Overall, the reviewed literature regarding the physicochemical properties of wood smoke particles provides a relatively clear picture of how these properties vary with the combustion conditions, whereas particle emissions from specific classes of combustion appliances are less well characterised. The major gaps in knowledge concern; (i) characterisation of the atmospheric transformations of wood smoke particles, (ii) characterisation of the physicochemical properties of wood smoke particles in ambient and indoor environments, and (iii) identification of the physicochemical properties that influence the biological effects of wood smoke particles.

  • 208.
    Boman, B Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Forsberg, A Bertil
    Järvholm, Bengt G
    Adverse health effects from ambient air pollution in relation to residential wood combustion2003In: Scandinavian Journal of Work, Environment and Health, Vol. 29, no 4, p. 251-260Article in journal (Refereed)
  • 209.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Particulate and gaseous emissions from residential biomass combustion2005Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Biomass is considered to be a sustainable energy source with significant potentials for replacing electricity and fossil fuels, not at least in the residential sector. However, present wood combustion is a major source of ambient concentrations of hydrocarbons (e.g. VOC and PAH) and particulate matter (PM) and exposure to these pollutants have been associated with adverse health effects. Increased focus on combustion related particulate emissions has been seen concerning the formation, characteristics and implications to human health. Upgraded biomass fuels (e.g. pellets) provide possibilities of more controlled and optimized combustion with less emission of products of incomplete combustion (PIC´s). For air quality and health impact assessments, regulatory standards and evaluations concerning residential biomass combustion, there is still a need for detailed emission characterization and quantification when using different fuels and combustion techniques.

    This thesis summarizes the results from seven different papers. The overall objective was to carefully and systematically study the emissions from residential biomass combustion with respect to: i) experimental characterization and quantification, ii) influences of fuel, appliance and operational variables and iii) aspects of ash and trace element transformations and aerosol formation. Special concern in the work was on sampling, quantification and characterization of particulate emissions using different appliances, fuels and operating procedures.

    An initial review of health effects showed epidemiological evidence of potential adverse effect from wood smoke exposure. A robust whole flow dilution sampling set-up for residential biomass appliances was then designed, constructed and evaluated, and subsequently used in the following emission studies. Extensive quantifications and characterizations of particulate and gases emissions were performed for residential wood and pellet appliances. Emission factor ranges for different stoves were determined with variations in fuel, appliance and operational properties. The emissions of PIC´s as well as PMtot from wood combustion were in general shown to be considerably higher compared to pellets combustion. PAHtot emissions were determined in the range of 1300-220000 µg/MJ for wood stoves and 2-300 µg/MJ for pellet stoves with phenantrene, fluoranthene and pyrene generally found as major PAH´s. The PM emissions from present residential appliances was found to consist of significant but varying fractions of PIC´s, with emissions in the range 35-350 mg/MJ for wood stoves compared to 15-45 mg/MJ for pellet stoves. Accordingly, the use of up-graded biomass fuels, combusted under continuous and controlled conditions give advantageous combustion conditions compared to traditional batch wise firing of wood logs. The importance of high temperature in well mixed isothermal conditions was further illustrated during pellets combustion to obtain complete combustion with almost a total depletion of PIC´s. Fine (100-300 nm) particles dominated in all studied cases the PM with 80-95% as PM1. Beside varying fractions of carbonaceous material, the fine PM consisted of inorganic volatilized ash elements, mainly found as KCl, K3Na(SO4)2 and K2SO4 with mass concentrations at 15-20 mg/MJ during complete combustion. The importance of the behavior of alkali elements for the ash transformation and fine particle formation processes was further shown, since the stability, distributions and compositions also directly control the degree of volatilization. In addition to the alkali metals, zinc was found as an important element in fine particles from residential biomass combustion. Finally, the behaviour of volatile trace elements, e.g. Zn and Cd, during pellets production and combustion were studied. A significant enrichment in the pellet fuel during the drying process was determined. The magnitude and importance of the enrichment was, however, relative small and some alternative measures for prevention were also suggested.

  • 210.
    Boman, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Forsberg, B
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Occupational and Environmental Medicine.
    Sandström, Thomas
    Umeå University, Faculty of Medicine, Department of Public Health and Clinical Medicine, Pulmonary Medicine.
    Shedding new light on wood smoke: a risk factor for respiratory health.2006In: Eur Respir J, ISSN 0903-1936, Vol. 27, no 3, p. 446-7Article in journal (Refereed)
  • 211.
    Boman, Christoffer
    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.
    Boström, Dan
    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.
    Characterization of inorganic particulate matter from residential combustion of pelletized biomass fuels2004In: Energy and Fuels, ISSN 0887-0624, Vol. 18, no 2, p. 338-348Article in journal (Refereed)
    Abstract [en]

    The increased focus on potential adverse health effects associated with exposure to ambient particulate matter (PM) motivates a careful characterization of particle emissions from different sources. Combustion is a major anthropogenic source of fine PM, and, in urban areas, traditional residential wood combustion can be a major contributor. New and upgraded biomass fuels have become more common, and fuel pellets are especially well-suited for the residential market. The objective of the present work was to determine the mass size distributions, elemental distributions, and inorganic-phase distributions of PM from different residential combustion appliances and pelletized biomass fuels. In addition, chemical equilibrium model calculations of the combustion process were used to interpret the experimental findings. Six different typical pellet fuels were combusted in three different commercial pellet burners (10−15 kW). The experiments were performed in a newly designed experimental setup that enables constant-volume sampling. Total-PM mass concentrations were measured using conventional filters, and the fractions of products of incomplete combustion and inorganic material were thermally determined. Particle mass size distributions were determined using a 13-step low-pressure cascade impactor with a precyclone. The PM was analyzed for morphology (using environmental scanning electron microscopy, ESEM), elemental composition (using energy-dispersive spectroscopy, EDS), and crystalline phases (using X-ray diffractometry, XRD). For complementary chemical structural characterization, time-of-flight secondary ion mass spectrometry (TOF−SIMS), X-ray photoelectron spectroscopy (XPS) and X-ray absorption fine structure (XAFS) spectroscopy were also used. The emitted particles were mainly found in the fine (<1 μm) mode with mass median aerodynamic diameters of 0.20−0.39 μm and an average PM1 of 89.5% ± 7.4% of total PM. Minor coarse-mode fractions (>1 μm) were present primarily in the experiments with bark and logging residues. Relatively large and varying amounts (28%−92%) were determined to be products of incomplete combustion. The inorganic elemental compositions of the fine particles were dominated by potassium, chlorine, and sulfur, with minor amounts of sodium and zinc. The dominating alkali phase was KCl, with minor but varying amounts of K3Na(SO4)2 and, in some cases, also K2SO4. The results showed that zinc is almost fully volatilized, subsequently and presumably forming a more complex solid phase than that previously suggested (ZnO). However, the formation mechanism and exact phase identification remain to be elucidated. With some constrains, the results also showed that the amounts and speciation of the inorganic PM seemed to be quite similar to that predicted by chemical equilibrium calculations.

  • 212.
    Boman, Christoffer
    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.
    Westerholm, Roger
    Pettersson, Esbjörn
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Evaluation of a constant volume sampling set-up for residential biomass fired appliances: influence of dilution conditions on particulate and PAH emissions2005In: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 29, no 4, p. 258-268Article in journal (Refereed)
    Abstract [en]

    Increased concerns about particulate matter (PM) and polycyclic aromatic hydrocarbons (PAH) emissions from residentialbiomass combustion and their potential health effects, motivates detailed emission measurements under controlled conditions. Traditional sampling in raw flue gases can suffer from drawbacks mainly related to transient flows and the condensable nature of organic compounds. Whole flow dilution with constantvolumesampling (CVS) is an alternative method but different samplingconditions may, however, influence the emission characteristics. The objective was to design a CVS system for emission measurements in residentialbiomassfiredappliances and determine the influence of dilutionsamplingconditions on the characteristics and distributions of PM and PAH. Softwood pellets were combusted in a pellet stove with variations in; dilution ratio (3–7x), sampling temperature (45–75 °C), dilution tunnel residence time (2–4 s) and fuel load (2.3 and 4.8 kW) according to a statistical experimental design. The samplingconditions did not influence either the emission concentrations of PM, CO and NO or the particle size distribution. Variations in residence time had no significant effect on any studied emission parameter. However, increased concentrations of organic gaseous carbon (OGC) and PAH were observed with increased dilution ratio. The distribution between particulate and semivolatile phase was influenced for 12 of the 37 analyzed PAH compounds, mainly by increased fractions of semivolatile material at higher sampling temperature. No influence of sampling temperature was observed for the concentrations of PAHtot or the dominating PAH compounds, i.e. phenanthrene, fluoranthene and pyrene. The results together with practical considerations also suggest sampling at 50±5 °C and 3–4 times dilution as robust and applicable conditions in the presently designed setup.

  • 213.
    Boman, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Pettersson, Esbjörn
    Lindmark, Fredrik
    Öhman, Marcus
    Nordin, Anders
    Westerholm, Roger
    Effects of temperature and residence time on emission characterstics during fixed-bed combustion of conifer stem-wood pellets.Manuscript (Other academic)
  • 214.
    Boman, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Applied Physics and Electronics.
    Pettersson, Esbjörn
    Nordin, Anders
    Westerholm, Roger
    Boström, Dan
    Gaseous and particulate emissions from combustion in residential wood log and pellet stoves-experimental characterization and quantificationManuscript (Other academic)
  • 215.
    Boman, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Pettersson, Esbjörn
    Energy Technology Centre, Piteå, Sweden.
    Westerholm, Roger
    Department of Analytical Chemistry, Arrhenius Laboratory, Stockholm University, Stockholm, Sweden.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Stove performance and emission characteristics in residential wood log and pellet combustion: Part 1: Pellet stoves2011In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 25, no 1, p. 307-314Article in journal (Refereed)
    Abstract [en]

    Stove performance, characteristics, and quantities of gaseous and particulate emissions were determined for two different pellet stoves, varying fuel load, pellet diameter, and chimney draft. This approach aimed at covering variations in emissions from stoves in use today. The extensive measurement campaign included CO, NOx, organic gaseous carbon, volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs), total particulate matter (PMtot) as well as particle mass and number concentrations, size distributions, and inorganic composition. At high load, most emissions were similar. For stove B, operating at high residual oxygen and solely with primary air, the emissions of PMtot and particle numbers were higher while the particles were smaller. Lowering the fuel load, the emissions of CO and hydrocarbons increased dramatically for stove A, which operated continuously also at lower fuel loads. On the other hand for stove B, which had intermittent operation at lower fuel loads, the emissions of hydrocarbons increased only slightly lowering the fuel load, while CO emissions increased sharply, due to high emissions at the end of the combustion cycle. Beside methane, dominating VOCs were ethene, acetylene, and benzene and the emissions of VOC varied in the range 1.1−42 mg/MJfuel. PAH emissions (2−340 μg/MJfuel) were generally dominated by phenanthrene, fluoranthene and pyrene. The PMtot values (15−45 mg/MJfuel) were in all cases dominated by fine particles with mass median diameters in the range 100−200 nm, peak mobility diameters of 50−85 nm, and number concentrations in the range 4 × 1013 to 3 × 1014 particles/MJfuel. During high load conditions, the particulate matter was totally dominated by inorganic particles at 15−25 mg/MJfuel consisting of potassium, sodium, sulfur, and chlorine, in the form of K2SO4, K3Na(SO4)2, and KCl. The study shows that differences in operation and modulation principles for the tested pellet stoves, relevant for appliances in use today, will affect the performance and emissions significantly, although with lower scattering in the present study compared to compiled literature data.

  • 216.
    Boman, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Schmidt, Florian M.
    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.
    Boström, Dan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ash transformation chemistry in biomass fixed beds with focus on slagging and aerosols: 20 years of research and new developments2017In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 254Article in journal (Other academic)
  • 217.
    Boman, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Trace element enrichment and behavior in wood pellet production and combustion processes.Manuscript (Other academic)
  • 218.
    Boman, Christoffer
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Luleå tekniska universitet.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Trace element enrichment and behaviour in wood pellet production and combustion processes2006In: Energy and Fuels, Vol. 20, p. 993-1000Article in journal (Refereed)
  • 219.
    Boman, Emil
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Korrosion i avfallsförbränningspannor: - med en fördjupad studie av korrosion på överhettare2012Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inspecta AB bedriver besiktning som en av deras huvudsysslor och besiktar värmekraftverket på Dåvamyran. Besiktning av pannan sker årligen. Detta är ett krav från arbetsmiljöverket genom AFS 2005:3 ”Besiktning av trycksatta anordningar”. Pannan gås igenom med avseende på säkerhet och kan om den inte anses uppfylla de ställda krav bli underkänd för drift. I besiktningen ingår besiktning av överhettartuberna och man har noterat att tuberna i överhettar 2 har börjat korrodera med en ökad hastighet.

    Anledningen till varför korrosionshastigheten ökat har inte kunnat fastställas, men en av anledningarna kan vara att sopsorteringen i samhället ökat. Problemen som uppstått kan man härleda till bränslet. Avfall är ett väldigt heterogent bränsle, vilket innebär att värmevärdet och sammansättningen varierar väldigt mycket. Detta leder till problem som orsakar kostsamma planerade och oplanerade stopp. För att minska problemen som uppstår kan man vidta åtgärder som att tillsätta additiv och byta tubmaterialet.

    Den korrosion som verifierades med hjälp av SEM/EDS-analysen var högtemperaturkorrosion i form av klorinducerad korrosion, detta ska dock inte ses som ett entydigt svar då endast en tub, som suttit på kanten av överhettaren blev analyserad. Den materialanalys som gjordes visade att materialstrukturen varit opåverkad.

    Umeå energi hade vidtagit tre åtgärder, vilka var att: skydda tubernas böjar med ett keramiskt material, sänka ångtemperaturen och byte av tubmaterial. Skyddet på tuberna visade sig inte fungerar då de slagits sönder av sotningen. Sänkningen av ångtemperaturen blev installerad 2011 och man hittade klorinducerade korrosion 2012 vilket leder till slutsatsen att den inte stoppat denna typ av korrosion. Materialet som Umeå energi hade valt till tuberna var Inconel 625 påsvetsad på ett låglegerat stål. Materialet har visat goda egenskaper i kloridrika miljöer och kommer högst sannolikt ge ett bra resultat, men till en initialt hög kostnad. En alternativ åtgärd skulle vara att prova att tillsätta svavel som additiv med bränslet. Det har visat sig ge bra resultat i tidigare studier.

  • 220.
    Bonthron, Jonatan
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Förstudie för etablering av vindkraft vid Dåva kraftvärmeverk2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
  • 221.
    Borg, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ny modell av lyftpunkt: En teoretisk och praktisk utredning av dess bärförmåga2017Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Lättelement AB designs and manufactures building elements in the form of ceilings, walls and floor tiles for the Nordic market. The majority are roof elements and the main market is Sweden. Each element has 4 lifting points. Lifting points are used for lifting elements, pulling together elements as well as attachment for fall protection equipment. Lättelement AB has designed a new model of lifting point that they want tested and intend to replace the current lifting point if the new model has the same or better capacity.

    The purpose of this work is to investigate if the new model of lifting point manages the forces that arise during its applications. This new model would facilitate the manufacture and assembly of lifting points.

    According to the theoretical calculations, the new model of lifting point would have better capacity than the current one. During tensile testing, unforeseen material failure were shown and the practical values ​​were significantly lower than expected. After tensile testing, the load capacity was calculated based on the current material failure and it was found that the calculations and test results are relatively well matched. Based on the requirements set for the new model of lifting point, the desired strength values ​​are not achieved to replace the current model.

    However, this work is a good basis for further development of the lifting point. Now it is known what happens at the material failure for this kind of lifting point. It provides an opportunity to construct a lifting point that will handle the desired capacity while at the same time being flexible from a production engineering perspective. 

  • 222.
    Borgström, Jonas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Mätning av hjulvarvshastighet med mikrokontroller2014Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
  • 223.
    Borén, Eleonora
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Off-gassing from thermally treated lignocellulosic biomass2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Off-gassing of hazardous compounds is, together with self-heating and dust explosions, the main safety hazards within large-scale biomass storage and handling. Formation of CO, CO2, and VOCs with concurrent O2 depletion can occur to hazardous levels in enclosed stored forest products. Several incidents of CO poisoning and suffocation of oxygen depletion have resulted in fatalities and injuries during cargo vessel discharge of forest products and in conjunction with wood pellet storage rooms and silos. Technologies for torrefaction and steam explosion for thermal treatment of biomass are under development and approaching commercialization, but their off-gassing behavior is essentially unknown.

    The overall objective of this thesis was to provide answers to one main question: “What is the off-gassing behaviour of thermally treated lignocellulosic biomass during storage?”. This was achieved by experimental studies and detailed analysis of off-gassing compounds sampled under realistic conditions, with special emphasis on the VOCs.

    Presented results show that off-gassing behavior is influenced by numerous factors, in the following ways. CO, CO2 and CH4 off-gassing levels from torrefied and stream-exploded biomass and pellets, and accompanying O2 depletion, are comparable to or lower than corresponding from untreated biomass. The treatments also cause major compositional shifts in VOCs; emissions of terpenes and native aldehydes decline, but levels of volatile cell wall degradation products (notably furans and aromatics) increase. The severity of the thermal treatment is also important; increases in torrefaction severity increase CO off-gassing from torrefied pine to levels comparable to emissions from conventional pellets, and increase O2 depletion for both torrefied chips and pellets. Both treatment temperature and duration also influence degradation rates and VOC composition. The product cooling technique is influential too; water spraying in addition to heat exchange increased CO2 and VOCs off-gassing from torrefied pine chips, as well as O2 depletion. Moreover, the composition of emitted gases co-varied with pellets’ moisture content; pellets of more severely treated material retained less moisture, regardless of their pre-conditioning moisture content. However, no co-variance was found between off-gassing and pelletization settings, the resulting pellet quality, or storage time of torrefied chips before pelletization. Pelletization of steam-exploded bark increased subsequent VOC off-gassing, and induced compositional shifts relative to emissions from unpelletized steam-exploded material. In addition, CO, CO2 and CH4 off-gassing, and O2 depletion, were positively correlated with the storage temperature of torrefied softwood. Similarly, CO and CH4 emissions from steam-exploded softwood increased with increases in storage temperature, and VOC off-gassing from both torrefied and steam-exploded softwood was more affected by storage temperature than by treatment severity. Levels of CO, CO2 and CH4 increased, while levels of O2 and most VOCs decreased, during storage of both torrefied and steam-exploded softwood.CO, CO2 and O2 levels were more affected by storage time than by treatment severity. Levels of VOCs were not significantly decreased or altered by nitrogen purging of storage spaces of steam-exploded or torrefied softwood, or controlled headspace gas exchange (intermittent ventilation) during storage of steam-exploded bark.

    In conclusion, rates of off-gassing of CO and CO2 from thermally treated biomass, and associated O2 depletion, are comparable to or lower than corresponding rates for untreated biomass. Thermal treatment induces shifts in both concentrations and profiles of VOCs. It is believed that the knowledge and insights gained provide refined foundations for future research and safe implementation of thermally treated fuels as energy carriers in renewable energy process chains.

  • 224.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Kajsa, Werner
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Pommer, Linda
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Defining the temperature regime of gaseous degradation products of Norway spruce2013In: 21nd European Biomass Conference and Exhibition, Copenhagen, June, 2013, ETA Florens Renewable Energies, 2013, 2013Conference paper (Other academic)
  • 225.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Industrial Doctoral School for Research and Innovation, Umeå University, Umeå, Sweden.
    Larsson, Sylvia H.
    Biomass Technology Centre, Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Andreas, Averheim
    Mikael, Thyrel
    Biomass Technology Centre, Department of Forest Biomaterials and Technology, Swedish University of Agricultural Sciences, Umeå, Sweden.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Reducing VOC off-gassing during the production of pelletized steam-exploded bark: impact of storage time and controlled ventilation2018In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 32, no 4, p. 5181-5186Article in journal (Refereed)
    Abstract [en]

    Volatile organic compound (VOC) off-gassing behavior of thermally treated biomass intended for bioenergy production has recently been shown to be vastly different from that of untreated biomass. Simple measures to reduce emissions, such as controlled ventilation and prolonged storage time, have been suggested but not yet studied in detail. In the present study, we monitored how VOC off-gassing was reduced over time (24–144 h) in enclosed storage with and without ventilation. Steam-exploded bark was collected directly from a pilot-scale steam explosion plant as well as before and after subsequent pelletizing. Active Tenax-TA absorbent sampling of VOCs was performed from the headspaces of a bench-scale sample storage setup. The impact of storage time and ventilation on VOC levels was evaluated through multivariate statistical analysis. The results showed that relative VOC concentrations in the headspace were reduced by increased storage time, with heavier VOCs reduced at a higher rate. VOC composition was neither reduced nor shifted by controlled intermittent ventilation during storage; instead, VOC levels equilibrated at the same levels as those stored without ventilation, and this was independent of the process step, storage time, or number of ventilations.

  • 226.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Averheim, Andreas
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Reducing VOCs off-gassing during production of pelletized steam exploded bark: impact of storage time and controlled ventilationManuscript (preprint) (Other academic)
    Abstract [en]

    VOC off-gassing behavior of thermally treated biomass intended for bioenergy production has recently been shown to be vastly different to that of untreated biomass. Simple measures to reduce emissions, such as controlled ventilation and prolonged storage time, has been suggested but not previously studied in detail. In the present study, we monitored how VOC off-gassing was reduced over time (24–144h) in closed storage with and without ventilation. Steam exploded bark was collected directly from a pilot scale steam explosion plant, and before and after subsequent pelletizing. Storage and active sampling of VOCs in the headspace was done in a bench-scale set-up using Tenax-TA absorbent. The impact of storage time and ventilation to reduce VOCs was evaluated through multivariate statistical analysis. The results showed that VOC concentrations in the headspace were reduced by increased storage time, and that heavier VOCs reduced faster. No impact on either reducing or shifting VOC composition could be achieved by controlled ventilation during storage; instead, VOCs emitted to the same concentrations anew, independent of process step, storage time, or number of ventilations.

  • 227.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University Industrial Doctoral School for Research and Innovation, Sweden.
    Larsson, Sylvia H.
    Thyrel, Mikael
    Averheim, Andreas
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    VOC off-gassing from pelletized steam exploded softwood bark: emissions at different industrial process steps2018In: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188, Vol. 171, p. 70-77Article in journal (Refereed)
    Abstract [en]

    Formation of hazardous gases during transport and storage of biomass for large-scale bioenergy production is an important safety concern. While off-gassing has been addressed in numerous studies for raw woody biomass, very few describe it in the context of biomass for bioenergy production pre-treated by thermal technologies such as steam explosion. Volatile Organic Components (VOCs) are expected to be altered by the treatment, but until now there is no research published on VOC profiles of steam exploded materials in industrial scale. In the present study, VOCs emitted from the products were evaluated by sampling from different production steps from steam explosion of softwood bark, and following the production chain including also pelletization. Off-gasses were actively sampled using Tenax TA absorbent and analyzed by GC–MS. The VOC formation dependency of operation and storage conditions at different process steps was evaluated by multivariate statistical analysis. We showed that the different process steps along the production line was the main influencing factor for VOC off-gassing amounts, with highest VOC levels directly after the steam explosion process. Treatment severity mainly altered the relative composition of VOC profiles with more terpenes emitted from milder treatment, whereas more severe treatment shifted VOCs composition to contain more furans, e.g. furfural. In summary, treatment by steam explosion leads to potentially problematic VOC off-gassing profiles from the material, and levels vary considerable along the production line. The findings are important from a fuel handling and working environment perspective.

  • 228.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Thyrel, Mikael
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Averheim, Andreas
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    VOC off-gassing from pelletized steam exploded softwood bark: emissions at different industrial process stepsIn: Fuel processing technology, ISSN 0378-3820, E-ISSN 1873-7188Article in journal (Refereed)
    Abstract [en]

    Formation of hazardous gases during transport and storage of biomass for large-scale bioenergy production is an important safety concern. While off-gassing has been addressed in numerous studies for raw woody biomass, very few describe it in the context of biomass for bioenergy production pre-treated by thermal technologies such as steam explosion. Volatile Organic Components (VOCs) are expected to be altered by the treatment, but until now there is no research published on VOC profiles of steam exploded materials in industrial scale. In the present study, VOCs emitted from the products were evaluated by sampling from different production steps from steam explosion of softwood bark, and following the production chain including also pelletization. Off-gasses were actively sampled using Tenax TA absorbent and analyzed by GC-MS. The VOC formation dependency of operation and storage conditions at different process steps was evaluated by multivariate statistical analysis. We showed that the different process steps along the production line was the main influencing factor for VOC off-gassing amounts, with highest VOC levels directly after the steam explosion process. Treatment severity mainly altered the relative composition of VOC profiles with more terpenes emitted from milder treatment, whereas more severe treatment shifted VOCs composition to contain more furans, e.g. furfural. In summary, treatment by steam explosion leads to potentially problematic VOC off-gassing profiles from the material, and levels vary considerable along the production line. The findings are important from a fuel handling and working environment perspective.

  • 229.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Rudolfsson, Magnus
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Pommer, Linda
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Off-gassing from 16 pilot-scale produced pellets assortments of torrefied pine: impact of torrefaction severity, storage time, pelletization parameters, and pellet qualityManuscript (preprint) (Other academic)
    Abstract [en]

    Off-gassing from wood pellets poses risks in large scale handling chains - yet little is known on off-gassing from pellets of torrefied wood. This study reports CO, CO2, and O2 concentrations in off-gases during storage of 16 torrefied and two untreated pellets assortments. According to an experimental design, pellets were produced in pilot scale from pine chips torrefied at five different set points. Off-gassing was assessed in relation to storage conditions, torrefaction and pelletization parameters, and pellet quality. Pellets from the most severely torrefied pine formed CO, CO2, and consumed O2 similarly to untreated pellets. Off-gassing was positively correlated to pellet moisture content; however, the most severely torrefied also retained the least moisture. Open air storage (20–270 days) of torrefied chips prior to pelletization did not affect off-gassing levels. Results are important for safe handling; torrefied pellets can cause comparable levels as untreated pellets of CO, CO2, and O2.

  • 230.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Rudolfsson, Magnus
    Nordin, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Pommer, Linda
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Off-gassing from pilot-scale torrefied pine wood chips: – impact of torrefaction severity, cooling technology, and storage timeManuscript (preprint) (Other academic)
    Abstract [en]

    During handling and storage of conventional wood-based energy carriers, O2 depletion as well as CO and CO2 off-gassing can reach hazardous levels, and certain irritating VOCs trespass exposure levels. When new thermally pre-treated biomass commodities are entering consumer markets, knowledge on these assortments’ off-gassing behaviour is needed. In this study, relative concentrations of VOCs, CO, CO2, and O2 in off-gases of five different pilot-scale torrefied pine wood chip assortments was monitored over 12 days. VOC composition shifted with increased torrefaction treatment; terpene concentrations decreased while furan and lignin derivates increased. Generally, VOC amounts decreased with storage time, but for the least severely torrefied chips (291°C, 6 min), certain VOCs increased; e.g. hexanal, acetone, and 2-pentylfuran. Torrefied chips was subject to two different cooling technologies: i) heat exchanging and ii) additional water spraying. Water spraying resulted in higher VOC concentrations, stronger O2 depletion, and higher CO2 by a factor four. 

  • 231.
    Borén, Eleonora
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Umeå University Industrial Doctoral School for Research and Innovation.
    Yazdanpanah, Fahimeh
    Lindahl, Roger
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Schilling, Christoph
    Chandra, Richard P.
    Ghiasi, Bahman
    Tang, Yong
    Sokhansanj, Shahabaddine
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Off-gassing of VOCs and permanent gases during storage of torrefied and steam exploded wood2017In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 31, no 10, p. 10954-10965Article in journal (Refereed)
    Abstract [en]

    Thermal treatment for upgrading of low-value feedstocks to improve fuel properties has gained large industrial interest in recent years. From a storage and transport perspective, hazardous off-gassing could be expected to decrease through the degradation of reactive biomass components. However, thermal treatment could also shift chemical compositions of volatile organic components, VOCs. While technologies are approaching commercialization, off-gassing behavior of the products, especially in terms of VOCs, is still unknown. In the present study, we measured off-gassing of VOCs together with CO, CO2, CH4, and O2 depletion from torrefied and steam exploded softwood during closed storage. The storage temperature, head space gas (air and N2), and storage time were varied. VOCs were monitored with a newly developed protocol based on active sampling with Tenax TA absorbent analyzed by thermal desorption-GC/MS. High VOC levels were found for both untreated and steam exploded softwood, but with a complete shift in composition from terpenes dominating the storage gas for untreated wood samples to an abundance of furfural in the headspace of steam exploded wood. Torrefied material emitted low levels of VOCs. By using multivariate statistics, it was shown that for both treatment methods and within the ranges tested, VOC off-gassing was affected first by the storage temperature and second by increasing treatment severity. Both steam exploded and torrefied biomass formed lower levels of CO than the reference biomass, but steam explosion caused a more severe O2 depletion.

  • 232.
    Bostedt, Nicklas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    NGN - Nästa Generations Nätverk (Krav och Målbild) för Piteå kommun2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    My work has been to develop a basis for Piteå Municipality's future investment on a newer and more modern IT-infrastructure. The report describes primarily the areas surrounding network segmentation, a new flexible WAN solution and a central policy engine with IEEE 802.1x. Through these implementations achieved a dynamic role-based access, a tool that all big organizations should have to tackle the challenges that have arisen over the last few years with BYOD (Bring Your Own Device).

    In order to achieve a more dynamic and segmented network, I have separated from layer 2 using MCE and L3VPN transport to various municipal sites, while I logically divided the network into different zones. Network optimization is today largely based on moving the intelligence from hardware to software, a so-called SDN (Software Defined Network). I have therefore chosen in this report to place great emphasis on describing the features of HP IMC, where new opportunities for control, management and logging of the network are presented and how they can optimize the operation of an organization.

    This work is a continuation of NGN – Nästa Generations Nätverk (Nätverks- och Riskanalys) för Piteå Kommun by Johan Carls.

  • 233.
    Boström, Dan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Lindström, Erika
    Boman, Christoffer
    Backman, Rainer
    Öhman, Marcus
    Grimm, Alejandro
    Ash transformation chemisty during energy conversion of agricultural biomass2009In: International Conference on Solid Biofuels, ICSB2009, Beijing, China, 2009Conference paper (Other academic)
  • 234.
    Boström, Dan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering.
    Grimm, Alejandro
    Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering.
    Ash transformation chemistry during energy conversion of biomass2010In: Impacts of Fuel Quality on Power Production and the Environment, Saariselkä, Finland, August 29–September 3, 2010, 2010Conference paper (Refereed)
  • 235.
    Boström, Dan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Eriksson, Gunnar
    Division of Energy Engineering, Department of Applied Physics and Mechanical Engineering, Luleå Technical University.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Division of Energy Engineering, Department of Applied Physics and Mechanical Engineering, Luleå Technical University.
    Ash transformations in fluidized-bed combustion of rapeseed meal2009In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 23, no 5, p. 2700-2706Article in journal (Refereed)
    Abstract [en]

    The global production of rapeoil is increasing. A byproduct is rapeseed meal that is a result of the oil extraction process. Presently the rapeseed meal mainly is utilized as animal feed. An interesting alternative use is, however, energy conversion by combustion. This study was undertaken to determine the combustion properties of rapeseed meal and bark mixtures in a bubbling fluidized bed, with emphasis on gas emissions, ash formation, -fractionation and -interaction with the bed material. Due to the high content of phosphorus in rapeseed meal the fuel ash is dominated by phosphates, in contrast to most woody biomass where the ash is dominated by silicates. From a fluidized bed combustion (FBC) point of view, rapeseed meal could be a suitable fuel. Considering FBC agglomeration effects, pure rapeseed meal is in level with the most suitable fuels, as earlier tested by the methods utilized in the present investigation. The SO2 emission, however, is higher than most woody biomass fuels as a direct consequence of the high levels of sulfur in the fuel. Also the particulate matter emission, both submicron and coarser particles, is higher. Again this can be attributed the high ash content of rapeseed meal. The high abundance of SO2 is apparently effective for sulfatization of KCl in the flue gas. Practically no KCl was observed in the particulate matter of the flue gas. A striking difference in the mechanisms of bed agglomeration for rapeseed meal compared to woody biomass fuels was also observed. The ubiquitous continuous layers on the bed grains found in FBC combustion of woody biomass fuels was not observed in the present investigation. Instead very thin and discontinuous layers were observed together with isolated partly melted bed ash particles. The latter could occasionally be seen as adhered to the quartz bed grains. Apparently the bed agglomeration mechanism, that obviously demanded rather high temperatures, involved more of adhesion by partly melted ash derived potassium -calcium phosphate bed ash particles/droplets than direct attack of gaseous alkali on the quartz bed grains forming potassium -calcium silicate rich bed grain layers. Am explanation could be found in the considerable higher affinity for base cations of phosphorus than silicon. This will to a great extent withdraw the present basic oxides from attacking the quartz bed grains with agglomeration at low temperatures as a result.

  • 236.
    Boström, Dan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Grimm, Alejandro
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics, Energy Technology and Thermal Process Chemistry.
    Björnbom, Emilia
    Chemical Engineering and Technology, Royal Institute of Technology, SE-100 44 Stockholm, Sweden.
    Öhman, Marcus
    Division of Energy Engineering, Luleå University of Technology, SE- 971 87 Luleå, Sweden.
    Influence of kaolin and calcite additives on ash transformations in small-scale combustion of oat2009In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 23, no 10, p. 5184-5190Article in journal (Refereed)
    Abstract [en]

    A growing interest has been observed for the use of cereal grains in small- and medium-scale heating. Previous studies have been performed to determine the fuel quality of various cereal grains for combustion purposes. The present investigation was undertaken in order to elucidate the potential abatement of low-temperature corrosion and deposits formation by using fuel additives (calcite and kaolin) during combustion of oat. Special emphasis was put on understanding the role of slag and bottom ash composition on the volatilization of species responsible for fouling and emission of fine particles and acid gases. The ash fractions were analyzed with scanning electron micro scopy/energy dispersive spectroscopy (SEM/EDS), for elemental composition, and with X-ray diffraction (XRD) for identification of crystalline phases. The previously reported K and Si capturing effects of kaolin additive were observed also in the present study using P-rich biomass fuels. That is, the prerequisites for the formation of low melting K-rich silicates were reduced. The result of using kaolin additive on the bottom ash was that no slag was formed. The effect of the kaolin additive on the formation of submicrometer flue gas particles was an increased share of condensed K-phosphates at the expense of K-sulfate and KCl. The latter phase was almost completely absent in the particulate matter. Consequently, the levels of HCl and SO2 in the flue gases increased somewhat. The addition of both calcite assortments increased the amount of farmed slag, although to a considerably higher extent for the precipitated calcite. P was captured to a higher degree in the bottom ash, compared to the combustion of pure oat. The effect of the calcite additives on the fine particle emissions in the flue gases was that the share of K-phosphate decreased considerably, while the content of K-sulfate and KCl increased. Consequently, also the flue-gas levels of acidic HCl and SO2 decreased. This implies that the low-temperature corrosion observed in small-scale combustion of oat possibly can be abated by employing calcite additives. Alternatively, if problems with slagging and deposition of corrosive matter at heat convection surfaces are to be avoided, kaolin additive can be utilized, on the condition that the higher concentrations of acidic gases can be tolerated.

  • 237.
    Boström, Dan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ash transformation chemistry during combustion of biomass, theory and technical applications2017In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 254Article in journal (Other academic)
  • 238.
    Boström, Dan
    et al.
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Grimm, Alejandro
    Luleå Univ Technol, Div Energy Sci, SE-97187 Luleå, Sweden.
    Boman, Christoffer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Öhman, Marcus
    Luleå Univ Technol, Div Energy Sci, SE-97187 Luleå, Sweden.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Backman, Rainer
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Ash Transformation Chemistry during Combustion of Biomass2012In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 26, no 1, p. 85-93Article in journal (Refereed)
    Abstract [en]

    There is relatively extensive knowledge available concerning ash transformation reactions during combustion of woody biomass. In recent decades, the use of these energy carriers has increased, from a low-technology residential small-scale level to an industrial scale. Along this evolution, ash chemical-related phenomena for woody biomass have been observed and studied. Therefore, presently the understanding for these are, if not complete, fairly good. However, because the demand for CO2-neutral energy resources has increased recently and will continue to increase in the foreseeable future, other biomasses, such as, for instance, agricultural crops, have become highly interesting. The ash-forming matter in agricultural biomass is rather different in comparison to woody biomass, with a higher content of phosphorus as a distinctive feature. The knowledge about the ash transformation behavior in these systems is far from complete. Here, an attempt to give a schematic but general description of the ash transformation reactions of biomass fuels is presented in terms of a conceptual model, with the intention to provide guidance in the understanding of ash matter behavior in the use of any biomass fuel, primarily from the knowledge of the concentrations of ash-forming elements. The model was organized in primary and secondary reactions. Restrictions on the theoretical model in terms of reactivity limitations and physical conditions of the conversion process were discussed and exemplified, and some principal differences between biomass ashes dominated by Si and P, separately, were outlined and discussed.

  • 239.
    Boström, Jesper
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Blockritningar och dess användning i produktion2011Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The project is an investigation for a new method creating blueprints for in-fill walls. The original purpose of the project was only to make a comparison between different types of methods creating these blueprints. During the beginning of the work I realized that it is hard to learn how to perform the new method, and therefore I have created a guide about the procedure of the work with the new method. This project is made in cooperation together with a construction company called Peab. The idea is that the blueprints for the in-fill walls in one of Peabs upcoming constructions are going to be created with the new method.

    The purpose with this work is to compare different type of methods creating blueprints for in-fill walls. The comparison is made for the three methods, AutoCAD, Revit and blueprints made by hand. The purpose with this project has also been to create a guide for the procedure of the work in Revit.

    The first part is a study that describes the subjects in this project. The internet and literature has been used for gathering information. The second part is the comparison. The result has been compared in the categories entry requirement, running time, equipment requirement, clarity/ accuracy of the blueprints and the information that is gained in the blueprints. The third and last part is the result of the guide, which is divided into six steps. Each step is described in words and with illustrations from Revit.

    The work is written in Swedish.

  • 240.
    Boström, Oskar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Metodik för högupplöst 3D-skanning av traktorer2016Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis on 3D-scanning includes a survey of the leading handheld scanners that are avaliable on the market today, together with two methodology parts. The client, Ålö, is a market leader in developing and manufacturing front loaders for the agricultural sector.  The 3D scanning technology will primarily be used to scan tractors that not yet have  a subframe to attach frontloaders on.

     

    The target with the benchmarking has been used to determine which one of the scanners, avaliable on the market today, that will fit Ålö’s needs and requirements best. Thus a number of criterias have been choosen in cooperation with the staff at Ålö and the scanners have been benchmarked towards these criterias.

     

    The methodology parts have basically been a large  number of practical tests in the basis before the necessary information were able to set through. These tests have been carried out in the factory at Ålö. To conduct these tests a variety of different objects had to be scanned to test the reliability. These objects are among others a free hanging subframe and a tractor with an already installed base.

     

    The aim with a good 3D scanning technology is to get competitive advantages versus other manufacturers competing on the same market as Ålö. This new technology will give faster time to market for new subframes, with increased quality, which in turn hopefully will increase sales of Ålö’s frontloaders.

  • 241. Bozaghian, Marjan
    et al.
    Rebbling, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Thyrel, Mikael
    Xiong, Shaojun
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics. Luleå University of Technology, Department of Engineering Sciences and Mathematics, Energy Engineering, S-971 87 Luleå, Sweden.
    Combustion characteristics of straw stored with CaCO3 in bubbling fluidized bed using quartz and olivine as bed materials2018In: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 212, p. 1400-1408Article in journal (Refereed)
    Abstract [en]

    The addition of Ca-containing compounds can reduce mass loss from agricultural biomass during storage. The resulting alkaline environment is detrimental to microorganisms present in the material. Theoretical analysis of Ca-containing biomass suggests that combustion properties are improved with respect to slagging. To validate the theoretical calculations, barley straw was utilized as a typical model agricultural biomass and combustion characteristics of straw pre-treated with 2 and 4 w/w% CaCO3 for combined improvement of storage and combustion properties were determined through combustion at 700 degrees C in a bench-scale bubbling fluidized-bed reactor (5 kW) using quartz and olivine sand as bed materials. The combustion characteristics were determined in terms of elemental composition and compound identification in bed ash and bed material including agglomerates, fly ash, particulate matter as well as flue gas measurements. The addition of CaCO3 to straw had both positive and negative effects on its combustion characteristics. Both additive levels raised the total de fluidization temperature for both quartz and olivine, and olivine proved to be less susceptible than quartz to reactions with alkali. With Ca-additives, the composition of deposits and fine particulate matter changed to include higher amounts of KCl potentially leading to higher risk for alkali chloride-induced corrosion. Flue gas composition was heavily influenced by CaCO3 additives by significantly elevated CO concentrations likely related to increased levels of gaseous alkali compounds. The results suggest that it is necessary to reduce gaseous alkali compounds, e.g. through kaolin or sulphur addition, if alkali-rich straw is to be co-combusted with Ca-rich biomass or large amounts of Ca-additives.

  • 242.
    Bozaghian, Marjan
    et al.
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology.
    Rebbling, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology.
    Xiong, Shaojun
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Combustion characteristics of barley straw stored with CaCO3 using olivine and quartz as bed materials in fluidized bed combustion2017Conference paper (Refereed)
  • 243.
    Bozaghian, Marjan
    et al.
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology.
    Rebbling, Anders
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Larsson, Sylvia H.
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology.
    Xiong, Shaojun
    Swedish University of Agricultural Sciences, Department of Forest Biomaterials and Technology.
    Skoglund, Nils
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Combustion characteristics of barley straw stored with CaCO3 using quartz and olivine as bed materials in fluidized-bed combustion2017Conference paper (Other academic)
  • 244.
    Brager, Eveliina
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Dimensionering av limträstomme till Coop butik: med en miljöjämförelse mellan stommaterialen stål och limträ2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The construction process in Sweden generates ten million carbon dioxide equivalents per year. Actors involved in the construction industry needs to clarify the climate load of the construction process and increase the knowledge of it. In this paper an alternative frame in glulam has been designed for a grocery store with a steel frame. As the bearing beam has a tensed three joint truss been used with a range of 40 meter. This work also includes an environmental comparison between steel and glulam as frame material set out from the amount of steel and glulam used in the frames, 31 ton of steel compared with 150 m3 glulam. The environmental analyses have been done by using the Eco strategy wheel, that is a tool used for optimizing a product regarding the environment, and by identifying environmental aspects from the manufacturing of the materials. The environmental aspects were then associated with the sustainability principles and graded by extent, severity and frequency. The ambition of this project was to show that a glulam frame can carry loads as good as a steel frame and to increase the knowledge of persons involved in the construction process to choose materials that are good for the environment. The results show that it was possible to design a glulam frame for the store but with an increased building height and volume as a consequence. Both frames could carry the loads but had different qualities. When the use of energy in the manufacture process were compared it showed that the glulam frame used almost twice the amount of energy compared to the steel frame, but in the process of manufacturing glulam almost all energy used came from renewable sources while the manufacturing of steel uses almost only energy from non-renewable sources. The carbon dioxide emission of the steel frame was 170 ton more than of the glulam frame that instead binds carbon dioxide. In the production of the steel frame the steel consumes 600 m3 more fresh water than the glulam frame and the steel process generate more waste. The transport of the steel frame also generates more carbon dioxide than the transport of the glulam, much thanks to the nearness of material and supplier of glulam to the construction site. This shows that it is good for the environment to think local.

  • 245.
    Brajerski, Thomas
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Stability design of multi-storey timber structures2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Stability design of buildings is an extremely important discipline within the field of structural engineering.

     

    This report demonstrates, with help of a worked example, the theory behind the stabilisation of multi-storey timber structures. The worked example is an existing 6-storey building, primarily made with cross laminated timber (CLT). The construction project is located in central Umeå and is designed and managed by Martinsons Byggsystem. The building uses an array of CLT wall panels as a stabilising system.

     

    A number of key points that will be looked at in the worked example; firstly, analysing the loads acting on the building, specifically the calculation of lateral wind loads and their effect on stabilising CLT panels; secondly, a deeper look into the methods of stabilisation using CLT walls. This will include the stability checks for overturning, sliding and shear and counter measures taken against any potential instability. Finally, a look into how CLT walls can be designed by hand calculations according to Eurocodes. There is no particular predefined method to do this, so this report will show how to design a CLT wall by treating CLT as either a homogeneous material or a non-homogeneous/composite material.

  • 246.
    Branca, Carmen
    et al.
    Istituto di Ricerche sulla Combustione, C.N.R., P.le V. Tecchio, 80125 Napoli, Italy.
    Di Blasi, Colomba
    Dipartimento di Ingegneria Chimica, dei Materiali e della Produzione Industriale, Università degli Studi di Napoli “Federico II”, P.le V. Tecchio, 80125 Napoli, Italy.
    Galgano, Antonio
    Istituto di Ricerche sulla Combustione, C.N.R., P.le V. Tecchio, 80125 Napoli, Italy.
    Broström, Markus
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Effects of the Torrefaction Conditions on the Fixed-Bed Pyrolysis of Norway Spruce2014In: Energy & Fuels, ISSN 0887-0624, E-ISSN 1520-5029, Vol. 28, no 9, p. 5882-5891Article in journal (Refereed)
    Abstract [en]

    Fixed-bed pyrolysis of Norway spruce wood previously subjected to torrefaction at temperatures between 533 and 583 K and retention times between 8 and 25 min was studied. Although the thermal pretreatment always results in an increased production of char at the expense of volatile products, appropriate torrefaction conditions give rise to maximum percentages of anhydrosugars, guaiacols possessing a carbonyl group, and phenols in the liquid fraction. Other carbohydrates (e.g., acetic acid, formic acid, hydroxyacetaldehyde, hydroxypropanone, furfural, and furfuryl alcohol) and the large majority of guaiacols show continuously decreasing values. The percentages of carbon monoxide and carbon dioxide in the gas product remain approximately the same, but that of methane slightly increases. The pyrolysis temperatures of torrefied wood are lower than those of the raw material, mainly because of the partial or complete absence of the exothermic contribution associated with extractives and hemicellulose degradation.

  • 247.
    Breimark, Odd
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Undersökning av förutsättningar för icke-publik laddinfrastruktur2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis is done as an assignment on behalf of Luleå Energi AB and Luleå Energi Elnät AB. It mainly concerns charging of Plug-in electric vehicles at corporations and apartment buildings. The object of this thesis is to investigate current requirements with these users and to investigate how services can be constructed to fulfil these requirements.

    To investigate the requirements of this non-public market a series of interviews were performed. A number of questions were constructed to use as ground during the interviews. Apart from the constructed questions, the interviewed were encouraged to express other opinions and questions concerning charging of electric vehicles. A large interest exists concerning this mater and several corporations are already offering charging although it also shows that a wider non-public infrastructure is required. The interviews also revealed that a wide spread of information is of importance and that charging with an ordinary home outlet (Schuko) is not to be recommended. All of the interviewed were of the opinion that more information from Luleå Energi would be of interest and that this would promote the expansion of electric vehicles.

    An extensive theory chapter was constructed to cover questions that may appear during the work of the thesis. This enabled a spread of information during the interviews. This chapter is meant to be used as information at Luleå Energi but could also be used as information to future clients. A number of criteria were constructed with the interviews and the theory chapter as foundation. These criteria were then given a weight of importance to present the aspects to bear in mind when implementing charge stations. The criteria that concerned standards and safety were the most important ones, along with the criteria of the impotence of an energy meter to every charging point. Criteria that where of importance but not as much as those mentioned earlier were limited access only to specific users, economical aspects, user friendly functions and effective payment systems. A confident ownership was of importance whereas some kind of service agreement could be of interest. Aspects of low importance were those connected to design but also the aspect that a connection for engine heaters is available.

    Charging of electric vehicles at apartment buildings and corporations will most likely not exceeded an output of 7.4 kW due to the fact that cars spend most of their time at parking spaces. These chargers could be complimented with chargers with a higher output up to 22 kW. The benefits of higher outputs appear when clients or workers spend a short time at a charging site. Quick chargers with outputs from 50 kW are rarely of economic benefit due to the high cost of the equipment and installation.

    A series of tests where concluded with a battery electric vehicle with the purpose to investigate energy consumption in Nordic winter climate. Temperature, travelled distance and energy consumption where the main parameters of the tests. The tests included both country road testing and city road testing. The tests resulted in a higher energy consumption and shorter range compared to the numbers presented from the car manufacturer. Despite this the test revealed that the range is enough in most of the cases with daily travel. The greatest advantages compared to fossil fuel vehicles appeared in city traffic where this particular vehicle could be driven in 3.5 hours without recharging. All together this reveals the economic and environmental advantages of driving a battery electric vehicle compared to a fossil fuel vehicle.

  • 248.
    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.

  • 249.
    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.

  • 250.
    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.

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