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  • 201.
    Hosain, Md Lokman
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. ABB AB, Corporate Research, Sweden.
    Domínguez, J. M.
    EPHYSLAB Environmental Physics Laboratory, Universidade de Vigo, Spain.
    Bel Fdhila, Rebei
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. ABB AB, Corporate Research, Västerås, Sweden.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Smoothed particle hydrodynamics modeling of industrial processes involving heat transfer2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 252, artikel-id 113441Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Smoothed Particle Hydrodynamics (SPH) is a mesh-free particle method that has been widely used over the past decade to model complex flows. The method has mainly been used to investigate problems related to hydrodynamics and maritime engineering, in which heat transfer does not play a key role. In this article, the heat-conduction equation is implemented in the open-source code DualSPHysics, based on the SPH technique, and applied to different study cases, including conduction in still water in a cavity, laminar water flow between two infinite parallel plates and tube bank heat exchanger. The thermal solutions obtained from SPH are benchmarked with the solutions from Finite Volume Method (FVM) and validated using available analytical solutions. DualSPHysics results are in good agreement with FVM and analytical models, and demonstrate the potential of the meshless approach for industrial applications involving heat transfer.

  • 202.
    Hosain, Md Lokman
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Domínguez, José
    University of VIGO, Spain.
    Crespo, Alejandro
    University of VIGO, Spain.
    Bel Fdhila, Rebei
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Smoothed Particle Hydrodynamics modeling of transient conduction and convection heat transferManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Smoothed Particle Hydrodynamics (SPH) is a mesh-free particle method that has been widely used in the last years to model some complex flows. SPH was mainly used to investigate problems related to hydrodynamics and maritime engineering where heat transfer is of no importance. Thermal problems have seldom been addressed due to the limitation of the main commercial and open-source SPH codes.

    In this article, the energy equation is implemented in the SPH based open-source code DualSPHysics to solve conduction and forced convection heat transfer problems. Laminar flow cases are simulated as the first validation cases of the implemented model. The studied cases include conduction in an aluminum block, conduction in still water in a cavity, laminar water flow between two infinite parallel plates and tube bank heat exchanger. The thermal solutions obtained from SPH are benchmarked with the solutions from Finite Volume Method (FVM) and also validated using available analytical solutions. The obtained results are in good agreement with FVM and available analytical models, which combined with the advantages of the meshless approach, show the high potential for industrial heat transfer applications.

    This development is an important step towards thermal optimization of several industrial applications that can’t benefit from the conventional FVM approach due to geometry or process complexities. The demonstrated SPH simulation and visualization capabilities contribute to build the future reliable energy-saving solutions.

  • 203.
    Hosain, Md Lokman
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. ABB AB Corp Res, Sweden.
    Fdhila, Rebei Bel
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. ABB AB Corp Res, Sweden.
    Literature Review of accelerated CFD Simulation Methods towards Online Application2015Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 75, s. 3307-3314Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Engineering advanced methods for example Computational Fluid Dynamics (CFD) are heavily used to solve, design and model complex industrial applications. They provide high accuracy however, the simulation time is too long and this limit its generalized use dramatically as for control purposes. CFD tools and methods are often used to analyze the energy distribution and management in different industrial processes like hot rolling industries, furnaces and boilers as well as a number of areas where mixing and thermal management are of importance. Huge amounts of energy are often fed into such processes. A small amount of optimization can provide a very large energy saving. It is now an urgent need to have a tool like real-time CFD to analyze, control and optimize on-line various industrial processes. This tool or method can contribute to build efficient and sustainable energy systems. The scope of this work is to find alternative simulation techniques that can also address industrial applications and provide solutions within a decent accuracy and resolution. In this paper we provide a literature review of those methods that can be categorized as mesh based, mesh free and hybrid that are capable of providing appropriate results in some key areas of interest. As a next step one of these methods will be implemented and coupled to CFD simulation of cooling impinging jets used to control the heat transfer and temperature behavior of a hot flat surface in a hot rolling process where thermal energy and cooling water are used with excess. (C) 2015 The Authors. Published by Elsevier Ltd.

  • 204.
    Hosain, Md Lokman
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Rönnberg, Kristian
    ABB AB, Corporate Research.
    Bel Fdhila, Rebei
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Air Flow inside Rotating Electrical Machines: A Comparison between Finite Volume and SPH Method2017Ingår i: Conference Proceedings of NAFEMS World Congress 2017 (NWC17), 2017Konferensbidrag (Refereegranskat)
    Abstract [en]

    A general, sufficiently accurate, applicable and reasonably fast approach to thermal analysis of rotating electrical machines is of high interest for motor and generator developers and manufacturers. The thermal performance and the lifetime of a machine is limited by the temperature distribution and the hot spot temperature. The most commonly encountered cooling medium is air and the temperature distribution is driven by the air flow pattern inside the machine. Two different Computational Fluid Dynamics methods, the mesh based Finite Volume Method (FVM) and the mesh free particle based Smoothed Particle Hydrodynamics (SPH) method are employed in this paper to model the airflow inside a rotating machine. Mesh based methods are quite robust, however, they are very expensive in terms of meshing effort and CPU time to be used extensively in R&D. Analysing and optimizing products with complex geometrical shapes need mesh generation for every specific design change and this may be the major part of the modelling process. This challenging task is not necessary for the SPH method. SPH method can also provide high quality 3D visualization that can improve the design process.

    This work investigates the usability of the SPH method when applied to rotating machinery for rotor speeds normally encountered in motors and generators. A comparison with an FVM based approach is also performed. Both the FVM and the SPH solvers show good agreement for the overall flow pattern inside the machine with some disagreement for the airflow inside the air-gap between the rotor and the stator. The FVM solver successfully captures the Taylor vortex flow inside the annulus air-gap which is in general a great modelling challenge. The SPH solver on the other hand shows great capability to couple rotation of the rotor and well represent the overall flow pattern inside the machine. However, the 3D SPH solver could not capture the complex Taylor vortices inside the air-gap which may be due to the limited number of particles used for the simulation. An increase in the number of particles would certainly improve the accuracy of the results as confirmed by the 2D SPH simulation. The present study shows that the SPH solver can be used to predict the air flow pattern inside rotating machines within an acceptable accuracy.

  • 205.
    Hosain, Md Lokman
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. ABB AB, Corporate Research, Sweden.
    Sand, U.
    ABB AB, Corporate Research, Sweden.
    Bel Fdhila, Rebei
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. ABB AB, Corporate Research, Sweden.
    Numerical Investigation of Liquid Sloshing in Carrier Ship Fuel Tanks2018Ingår i: IFAC-PapersOnLine, ISSN 2405-8963, Vol. 51, nr 2, s. 583-588Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Liquid sloshing inside a partially filled tank has a great impact on the fragile internal tank coating and also on the stability of carrier ships. Several studies highlighted the challenges encountered due to the sloshing and proposed anti-sloshing tank structures. However, sloshing of liquefied natural gas fuel in high pressure vessels during transportation still remain a challenge. In the present numerical study we consider a downscaled 2D geometry to investigate the sloshing. Non-dimensional numbers are used to downscale the geometry. The purpose is to understand the flow structures and validate the downscaling approach based on the similarity scale laws. In the present work, Computational Fluid Dynamics (CFD) based on the Reynolds Averaged Navier-Stokes equations (RANS) with the Volume of Fluid (VOF) method in one hand and the Smooth Particle Hydrodynamics (SPH) method in the other hand, are used to simulate the downscaled model. The results from both methods are compared and validated using experimental data. A full scale model have also been simulated using SPH to verify the applicability of the scaling laws. The SPH model shows the capability to efficiently capture the sloshing phenomena. The VOF and SPH provide similar results in terms of flow dynamics, pressure and forces. The overall numerical results agree with the measurements and show that SPH can be an efficient tool to be used in modelling sloshing phenomena, compared to the RANS-VOF approach which is expensive in terms of CPU time. However, features like turbulence need to be further investigated. 

  • 206.
    Hu, Y.
    et al.
    Cranfield University, Bedford, United Kingdom.
    Tewari, A.
    Cranfield University, Bedford, United Kingdom.
    Varga, L.
    Cranfield University, Bedford, United Kingdom.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology, Stockholm, Sweden.
    System dynamics of oxyfuel power plants with liquid oxygen energy storage2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 3727-3733Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Traditional energy storage systems have a common feature: the generating of secondary energy (e.g. electricity) and regenerating of stored energy (e.g. gravitational potential, and mechanical energy) are separate rather than deeply integrated. Such systems have to tolerate the energy loss caused by the second conversion from primary energy to secondary energy. This paper is concerned with the system dynamics of oxyfuel power plants with liquid oxygen energy storage, which integrates the generation of secondary energy (electricity) and regeneration of stored energy into one process and therefore avoids the energy loss caused by the independent process of regeneration of stored energy. The liquid oxygen storage and the power load of the air separation unit are self-adaptively controlled based on current-day power demand, day-ahead electricity price and real-time oxygen storage information. Such an oxyfuel power plant cannot only bid in the day-ahead market with base load power but also has potential to provide peak load power through reducing the load of the air separation unit in peak time. By introducing reasoning rules with fuzzy control, the oxygen storage system has potential to be further extended by integrating renewable energy resources into the system to create a cryogenic energy storage hub. 

  • 207.
    Hu, Yukun
    et al.
    Royal Inst Technol.
    Li, Hailong
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Techno-economic evaluation of the evaporative gas turbine cycle with different CO(2) capture options2012Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 89, nr 1, s. 303-314Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The techno-economic evaluation of the evaporative gas turbine (EvGT) cycle with two different CO(2) capture options has been carried out. Three studied systems include a reference system: the EvGT system without CO(2) capture (System I), the EvGT system with chemical absorption capture (System II), and the EvGT system with oxyfuel combustion capture (System III). The cycle simulation results show that the system with chemical absorption has a higher electrical efficiency (41.6% of NG LHV) and a lower efficiency penalty caused by CO(2) capture (10.5% of NG LHV) compared with the system with oxyfuel combustion capture. Based on a gas turbine of 13.78 MW, the estimated costs of electricity are 46.1 $/MW h for System I. while 70.1 $/MW h and 74.1 $/MW h for Systems II and III, respectively. It shows that the cost of electricity increment of chemical absorption is 8.7% points lower than that of the option of oxyfuel combustion. In addition, the cost of CO(2) avoidance of System II which is 71.8 $/tonne CO(2) is also lower than that of System III, which is 73.2 $/tonne CO(2). The impacts of plant size have been analyzed as well. Results show that cost of CO(2) avoidance of System III may be less than that of System II when a plant size is larger than 60 MW.

  • 208.
    Hu, Yukun
    et al.
    Royal Inst Technol .
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Li, Hailong
    Effects of flue gas recycle on oxy-coal power generation system2012Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 97, nr SI, s. 255-263Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper examined and assessed various configuration options about emission removal including particles. SOx and NOx in an oxy-coal combustion system for CO2 capture. A performance analysis was conducted in order to understand the impacts of those options concerning process design, process operation and system efficiency. Results show that different flue gas recycle options have clear effects on the emissivity and absorptivity of radiating gases in boiler due to the change of flue gas compositions. The maximum difference amongst various options can be up to 15% and 20% for emissivity and absorptivity respectively. As a result, the heat transfer by radiation can vary about 20%. The recycle options also have impacts on the design of air heater and selective-catalytic-reduction (SCR) preheater. This is due to that the largely varied operating temperatures in different options may result in different required areas of heat exchangers. In addition, the dew point of flue gas and the boiler efficiency are affected by the configurations of flue gas recycle as well.

  • 209.
    Huang, C.
    et al.
    Tongji University, Shanghai, China.
    Li, Y.
    Tongji University, Shanghai, China.
    Li, X.
    Tongji University, Shanghai, China.
    Wang, H.
    Tongji University, Shanghai, China.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Institute of Technology (KTH), Sweden.
    Wang, X.
    Tongji University, Shanghai, China.
    Wu, J.
    Tongji University, Shanghai, China.
    Li, F.
    Tongji University, Shanghai, China.
    Understanding the water-energy nexus in urban water supply systems with city features2018Ingår i: Energy Procedia, Elsevier Ltd , 2018, s. 265-270Konferensbidrag (Refereegranskat)
    Abstract [en]

    The water-energy nexus has been introduced into urban water supply systems (WSSs) to improve the current plight of scarce resources and greenhouse effect in recent years. Urban water-energy integrated management is limited by the characteristics and reality of each city. In this paper, we characterize the comprehensive influence factors of energy use in China urban WSSs including geographic differences and city forms. The results indicate that the pressure of pipeline network and plain area ratio restricted by geomorphology would significantly impact the energy consumption during conveyance and distribution stage. For the city form aspect, the total volume of urban water supply and the leakage rate of pipeline networks play important roles in energy consumption of urban WSSs in China. In this study, the specific electricity consumption in WSSs was quantified, and several factors affected by city features which show strong correlation with energy use were determined. The results are of great significance to the energy saving in water supply systems in urban areas.

  • 210.
    Huang, J.
    et al.
    East China University of Science and Technology, Shanghai, China.
    Yang, J.
    East China University of Science and Technology, Shanghai, China.
    Yu, X.
    East China University of Science and Technology, Shanghai, China.
    Tu, S. -T
    East China University of Science and Technology, Shanghai, China.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Energy-efficient extraction of fuel from chlorella combined with CO2 capture2014Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 61, s. 2805-2808Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    To combine the abilities of lipids extraction and CO2 capture by algae + IL system, chlorella hydrolysis integrating CO2 removal by ILs ([bmim][BF4], [bmim]Cl and [amim]Cl) to extract lipids energy-efficiently was demonstrated in this study. The addition of CO2 to [bmim][BF4] can increase the lipids yield from 14.2% to 15.6%. The value of net energy gain increased from 10.4 to 35.9 with the CO2 addition to [bmim][BF4] because of the compensated CO2 capture energy in the algae extraction process.

  • 211.
    Hui, Hongxun
    et al.
    Zhejiang Univ, Peoples R China..
    Ding, Yi
    Zhejiang Univ, Peoples R China..
    Shi, Qingxin
    Univ Tennessee, Dept Elect Engn & Comp Sci, Knoxville, TN 37996 USA..
    Li, Fangxing
    Univ Tennessee, USA..
    Song, Yonghua
    Zhejiang Univ, Peoples R China.;Univ Macau, Peoples R China..
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. KTH Royal Inst Technol, Stockholm, Sweden..
    5G network-based Internet of Things for demand response in smart grid: A survey on application potential2020Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 257, artikel-id UNSP 113972Artikel, forskningsöversikt (Refereegranskat)
    Abstract [en]

    Demand response (DR) has been widely regarded as an effective way to provide regulation services for smart grids by controlling demand-side resources via new and improved information and communication technologies. Emerging 5G networks and 5G-based Internet of Things (IoTs) can doubtless provide better infrastructure for DR, owing to 5G's advantages of fast transfer speed, high reliability, robust security, low power consumption, and massive number of connections. However, nearly none of the existing studies have applied 5G technology to DR, which will be the subject surveyed in this paper. First, the concept of DR and recent practical advances are investigated, especially the application of communication technologies to DR. Then, a comprehensive review of the cyber security, consumer privacy, and reliability of DR is presented. These topics received little attention in the past, but they will be among the most crucial factors in the future. In addition, the essential features and typical application scenarios of 5G communication are investigated. On this basis, the advantages, methods, recent advances, and implementation planning of 5G on DR are studied. Finally, the future work that must urgently be conducted in order to achieve the application of 5G to DR is discussed. This paper's application survey of 5G on DR is carried out before 5G technology enters the large-scale commercial stage, so as to provide references and guidelines for developing future 5G networks in the smart grid paradigm.

  • 212.
    Häggstål, Daniel
    et al.
    Mälardalens högskola, Institutionen för matematik och fysik.
    Kvarnström, Andreas
    Mälardalens högskola, Institutionen för matematik och fysik.
    Dotzauer, Erik
    Mälardalens högskola, Institutionen för matematik och fysik.
    Holmström, Kenneth
    Mälardalens högskola, Institutionen för matematik och fysik.
    Fuel mix optimization of combined heat and power production utilizing a simulation model2004Konferensbidrag (Refereegranskat)
  • 213.
    Inayat, A.
    et al.
    Department of Sustainable and Renewable Energy Engineering, University of Sharjah, Sharjah, United Arab Emirates.
    Ghenai, C.
    Department of Sustainable and Renewable Energy Engineering, University of Sharjah, Sharjah, United Arab Emirates.
    Naqvi, Muhammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Ammar, M.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
    Ayoub, M.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
    Hussin, M. N. B.
    Chemical Engineering Department, Universiti Teknologi PETRONAS, Bandar Seri Iskandar, Perak, Malaysia.
    Parametric Study for Production of Dimethyl Ether (DME) As a Fuel from Palm Wastes2017Ingår i: Energy Procedia, Elsevier Ltd , 2017, s. 1242-1249Konferensbidrag (Refereegranskat)
    Abstract [en]

    Dimethyl Ether (DME) has been getting numerous attention as it's potential as the second generation bio-fuel. Traditionally DME is produced from the petroleum based stock which involves two steps of synthesis (methanol synthesis from the syngas and DME synthesis from methanol). DME synthesis via single step is one of the promising methods that has been developed. In Malaysia, due to the abundance of oil palm waste, it is a good candidate to be used as a feedstock for DME production. In this paper, single step process of DME synthesis was simulated and investigated using the Aspen HYSYS. Empty Fruit Bunch (EFB) from palm wastes has been taken as the main feed stock for DME synthesis. Four parameters (temperature, pressure, steam/biomass ratio and oxygen/biomass ratio) have been studied on the H2/CO ratio and DME yield. The results showed that optimum H2/CO ratio of 1.0 has been obtained when having an oxygen to biomass ratio (O/B) of 0.37 and steam to biomass ratio (S/B) of 0.23. The increment in the steam to biomass ratio increased the production of DME while the increment in oxygen to biomass ratio will cause reduction in DME production. © 2017 The Authors.

  • 214.
    Ingason, Haukur
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Kumm, Mia
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Nilsson, Daniel
    LTH.
    Lönnermark, Anders
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Claesson, Alexander
    SP.
    Li, Ying Zhen
    SP.
    Fridolf, Karl
    LTH.
    Åkerstedt, Rolf
    SL.
    Nyman, Hans
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Dittmer, Torkel
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Forsén, Rickard
    FOI.
    Janzon, Bo
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Meyer, Gero
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Bryntse, Anders
    FOI.
    Carlberg, Tobias
    FOI.
    Newlove-Eriksson, Lindy
    FHS.
    Palm, Anders
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    The Metro Project: Final report2012Rapport (Övrigt vetenskapligt)
    Abstract [en]

    This report compiles the results from the METRO project. The different parts of theproject – design fires, evacuation, integrated fire control, smoke control, extraordinarystrain onconstructions and fire- and rescue operations – are presented separately.

    The most complicated and expensive part of the project was the performance of thelarge scale fire and explosion tests in the Brunsberg tunnel, where the maximum heatrelease rates measured from the metro wagon was 77 MW.

    The main results from the project are new recommendations regarding design firesin mass transport systems, identification of key factors for fire and smoke spread in tunnelsand at stations as well as regarding the difficulties for disabled persons to evacuatefrom trains in tunnels, new recommended types of way guiding systems, safer design incase of explosions in trains and evaluation of the fire and rescue services’ possibilitiesand limitations in underground mass transport systems.

  • 215.
    Jalilzadehazhari, Elaheh
    et al.
    Linnaeus University, Växjö, Sweden.
    Vadiee, Amir
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Johansson, Peter
    Jönköping University, Sweden.
    Achieving a trade‐off construction solution using BIM, an optimization algorithm, and a multi‐criteria decision‐making method2019Ingår i: Buildings, ISSN 2075-5309, E-ISSN 2075-5309, Vol. 9, nr 4, s. 1-14, artikel-id 81Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Energy Performance of Building Directive obligated all European countries to reduce the energy requirements of buildings while simultaneously improving indoor environment quality. Any such improvements not only enhance the health of the occupants and their productivity, but also provide further economic benefits at the national level. Accomplishing this task requires a method that allows building professionals to resolve conflicts between visual and thermal comfort, energy demands, and life-cycle costs. To overcome these conflicts, this study exploits the incorporation of building information modelling (BIM), the design of experiments as an optimization algorithm, and the analytical hierarchy process (AHP) into a multi-criteria decision-making method. Any such incorporation can (i) create constructive communication between building professionals, such as architects, engineers, and energy experts; (ii) allow the analysis of the performance of multiple construction solutions with respect to visual and thermal comfort, energy demand, and life-cycle costs; and (iii) help to select a trade-off solution, thereby making a suitable decision. Three types of energy-efficient windows, and five types of ground floors, roofs, and external wall constructions were considered as optimization variables. The incorporation of several methods allowed the analysis of the performance of 375 construction solutions based on a combination of optimization variables, and helped to select a trade-off solution. The results showed the strength of incorporation for analyzing big-data through the intelligent use of BIM and a simulation in the field of the built environment, energy, and costs. However, when applying AHP, the results are strongly contingent on pairwise comparisons.

  • 216.
    Jansson, Andreas
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Hårdare utsläppskrav för medelstora förbränningsanläggningar: En utredning om MCP-direktivets relevans, innebörd och konsekvenser för Mälarenergi och dess anläggningar.2016Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    EU har beslutat om ett nytt direktiv som innebär hårdare krav för mellanstora förbränningsanläggningar. Detta direktiv innebär hårdare utsläppskrav och när dessa nya gränser skall efterföljas 2025 eller 2030 är Mälarenergi ett företag som kommer att drabbas. Detta arbete har gått ut på att ta reda på vad detta direktiv kommer att få för konsekvenser för Mälarenergis 24 stycken spetslastpannor.

    Arbetet har gått ut på att sammanställa befintliga underlag för att kunna besvara frågan om vad direktivet kommer att få för inverkan. Direktivet behandlar stoft, NOx och SOx och där mätningar tidigare har genomförts har de granskats.

    Utredningen har kunnat visa på att av dessa 24 pannor är det 2 pannor som ej kommer klara gränsvärdena för stoft. På dessa två pannor har ytterligare mätningar genomförts och resultatet har verifierats. Dessutom genomfördes en gasanalys av ett Fourier transform infrared spectroscopy av en panna samt en energibalansberäkning.

    Det finns olika metoder för att minska stoften på dessa pannor men de varierar i pris. Exempel på detta är att installera elektrofilter eller slangfilter, men kostnaden uppgår till över 800 000kr i investeringskostnader. Ett alternativ är ett additiv som heter Kaolin, där undersökningar har visat att till en kostnad av ca 45000 kr per år torde stofthalten kunna minskas till under gränsvärdena.

    En energibalansberäkningen har genomförts och visar på att pelletspannan i Kungsör har en verkningsgrad på 91% vilket stämmer överrens med vad leverantören anger.

  • 217.
    Ji, X.
    et al.
    Royal Institute of Technology, Sweden.
    Yan, Jinyue
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling. Royal Institute of Technology, Sweden.
    Thermodynamic properties for humid gases from 298 to 573 K and up to 200 bar2006Ingår i: Applied Thermal Engineering, ISSN 1359-4311, E-ISSN 1873-5606, Vol. 26, nr 2-3, s. 251-258Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    For the needs of process design, the model proposed in our previous papers was extended to calculate the thermodynamic properties of humidity, heat capacity, molar volume, partial pressure of water vapour, enthalpy and entropy for humid gases (nitrogen, oxygen, air or a nitrogen-oxygen mixture). The comparison with other models from 300 to 473 K and I to 100 bar shows that the results calculated with different models are consistent within 50 bar and 400 K; out of this range, there is some difference. Meanwhile, mole ratios of nitrogen to oxygen in the saturated humid air were calculated from 323 to 523 K and 50 to 250 bar. It is found that the mole ratio of nitrogen to oxygen keeps almost constant, and the effect of the slight changes in the ratio of nitrogen to oxygen on the humidity, enthalpy and entropy of humid air is small enough to be neglected. Moreover, the enthalpy of dry air was predicted, and the comparison with other models again proved the reasonable assumptions and prediction capability of the new model. (c) 2005 Elsevier Ltd. All rights reserved.

  • 218.
    Jiang, Xi
    et al.
    Univ Lancaster, Dept Engn, Chair Energy Use & Transport, Lancaster LA1 4YR, England..
    Kraft, Markus
    Univ Cambridge, Cambridge CB2 1TN, England..
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Royal Inst Technol, Stockholm, Sweden.
    Selected papers from the Twelfth International Conference on Combustion and Energy Utilisation (12th ICCEU) Preface2015Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 156, s. 747-748Artikel i tidskrift (Övrigt vetenskapligt)
  • 219. Jianguo, Li
    et al.
    Shaokai, Zhang
    Li, Hailong
    Mälardalens högskola, Akademin för innovation, design och teknik. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Xinhua, Ouyang
    Liulian, Huang
    Yonghao, Ni
    Lihui, Chen
    Cellulase pretreatment for enhancing cold caustic extraction-based separation of hemicelluloses and cellulose from cellulosic fibers2018Ingår i: Bioresource Technology, ISSN 0960-8524, E-ISSN 1873-2976, Vol. 251, s. 1-6Artikel i tidskrift (Refereegranskat)
  • 220.
    Jin, Hongguang
    et al.
    nstitute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing, China.
    Gao, L.
    nstitute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, China.
    Han, W.
    nstitute of Engineering Thermophysics, Chinese Academy of Sciences, Beijing 100080, China.
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    A new approach integrating CO2 capture into a coal-based polygeneration system of power and liquid fuel2007Ingår i: Proceedings of the ASME Turbo Expo, 2007, s. 311-321Konferensbidrag (Refereegranskat)
    Abstract [en]

    Reducing the energy penalty for CO2 Capture and Storage (CCS) is a challenge. Most of previous studies for CCS have been focused on power generation system. When CCS is included in the polygeneration system, a new methodology that jointly considering CCS and liquid fuel production should be introduced. In this paper, we proposed a new approach integrating CCS into a coal-based polygeneration system for power generation and methanol production: the syngas produced from the coal gasifier, without adjusting the composition (CO/H2 ratio) by shift reaction, is used to synthesis methanol directly. Moreover, the partial-recycle scheme, in which a part of unreacted gas is recycled back to the synthesis reactor, is adopted in the synthesis unit. Another part of unreacted gas is treated to remove CO2, and then is used as clean fuel for the power generation subsystem. Compared to the conventional CCS approaches adopted by the power generation systems, the new approach is mainly characterized by two features: firstly, the combination of the removal of the composition adjustment process and a partial-recycle scheme can not only reduces the energy consumption for methanol production, but also obtains a high concentration of COx (CO and CO2) in the unreacted gas; secondly, the CO2 is captured from the unreacted gas, instead of from syngas generated by the gasifier. Due to increment of CO x concentration, the new approach can reduce the energy consumption for CO2 capture compared to conventional pre-combustion CO 2 capture. In the conventional coal based IGCC systems, the thermal efficiency is around 34-36% for a case with CO2 capture and around 44% for a case without CO2 capture. However, with the innovative approach integrating CCS, the polygeneration system in this paper can achieve the equivalent thermal efficiency as high as 47% when 72% of CO2 is recovered, which provides a significant improvement for CO2 capture. It's clearly that the new approach can increase the thermal efficiency, instead of incurring an energy penalty for CO2 capture. The results achieved in this study have provided a new methodology integrating CO2 capture into the polygeneration system, which reveals the different characteristics compared to power-generation system that has been overlooked by the previous studies.

  • 221.
    Jin, Ming
    et al.
    Univ Calif Berkeley, Dept Ind Engn & Operat Res, Berkeley, CA 94720 USA..
    Jain, Rishee
    Stanford Univ, Dept Civil & Environm Engn, Stanford, CA 94305 USA..
    Spanos, Costas
    Univ Calif Berkeley, Dept Elect Engn & Comp Sci, Berkeley, CA 94720 USA..
    Jia, Qingshan
    Tsinghua Univ, Dept Automat, Beijing, Peoples R China..
    Norford, Leslie K.
    MIT, Dept Architecture, Cambridge, MA 02139 USA..
    Kjaergaard, Mikkel
    Univ Southern Denmark, Maersk McKinney Moller Inst, Odense, Denmark..
    Yan, Jinyue
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Energy-cyber-physical systems2019Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 256, artikel-id UNSP 113939Artikel i tidskrift (Övrigt vetenskapligt)
  • 222.
    Jiyang, Xie
    et al.
    Beijing University of Posts and Telecommunications, China.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Zhanyu, Ma
    Beijing University of Posts and Telecommunications, China..
    Qie, Sun
    Shandong University, China.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för innovation, design och teknik, Inbyggda system.
    Zhongwei, Si
    Beijing University of Posts and Telecommunications, China.
    Jun, Guo
    Beijing University of Posts and Telecommunications, China.
    Analysis of Key Factors in Heat Demand Prediction with Neural Networks2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 105, s. 2965-2970Artikel i tidskrift (Refereegranskat)
    Abstract [sv]

    The development of heat metering has promoted the development of statistic models for the prediction of heat demand, due to the large amount of available data, or big data. Weather data have been commonly used as input in such statistic models. In order to understand the impacts of direct solar radiance and wind speed on the model performance comprehensively, a model based on Elman neural networks (ENN) was adopted, of which the results can help heat producers to optimize their production and thus mitigate costs. Compared with the measured heat demand, the introduction of wind speed and direct solar radiation has opposite impacts on the performance of ENN and the inclusion of wind speed can improve the prediction accuracy of ENN. However, ENN cannot benefit from the introduction of both wind speed and direct solar radiation simultaneously. 

  • 223.
    Johansson, Eva-Maj
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Beslutsunderlag för biogasproduktion: Teknikkartläggning över biogasprocessen2012Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 224.
    Johansson, Robin
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    DIMENSIONERING AV NY FJÄRRVÄRMEPANNA: Vid Craboverket i Fagersta2012Självständigt arbete på grundnivå (högskoleexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
  • 225.
    Jurasz, Jakub
    et al.
    Mälardalens högskola.
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    The potential of photovoltaic systems to reduce energy costs for office buildings in time-dependent and peak-load-dependent tariffs2019Ingår i: Sustainable cities and society, ISSN 2210-6707, Vol. 44, s. 871-879Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Electrical power generation across the world is facing dramatic changes for a variety of reasons related to reliability, economics and environmental concerns. Over recent years a significant increase has been observed in installed capacity of photovoltaic systems. Due to their typical seasonal and diurnal energy conversion patterns their integration into power systems creates new opportunities as well as threats. This paper intends to show how photovoltaics can contribute to reducing peak load in office buildings and thereby minimise expenditure on electricity during time- and peak-load-dependent energy prices/tariffs. An additional benefit is also provided to the national power system by reducing the need for peaking power stations. The calculations are performed for energy tariffs commonly used for commercial buildings in Poland. The simulation relies on climatic and price data for 2016. The results show significant potential for photovoltaics to reduce the peak load (from almost 60 kW to slightly over 44 kW) whilst simultaneously minimising energy costs to the building (from 1.2% up to 5.8% depending on the selected tariff). This study demonstrates the economic benefits of using PV system for reducing peak loads. A sensitivity analysis with regard to photovoltaics investment costs is carried out showing that the increasing investment costs have different impact on total energy cost depending on the considered energy tariff.

  • 226.
    Jurasz, Jakub K.
    et al.
    AGH Univ Sci & Technol, Al A Mickiewicza 30, PL-30059 Krakow, Poland.;Malardalen Univ, Hgsk Plan 1, S-72220 Vasteras, Sweden..
    Dabek, Pawel B.
    Wroclaw Univ Environm & Life Sci, Ul CK Norwida 25, PL-50375 Wroclaw, Poland..
    Campana, Pietro Elia
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Can a city reach energy self-sufficiency by means of rooftop photovoltaics?: Case study from Poland2020Ingår i: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 245, artikel-id 118813Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The process of decarbonising economies has to take place on multiple levels. One of the objectives is to ensure renewables-based energy self-sufficiency of cities. Cities have become home to the majority of the world's population, and at the same time contribute enormously to environmental pollution. Considering the above, the purposes of this paper are threefold: to formulate a methodology for estimating rooftop photovoltaics (PV) potential in urban areas based on detailed Light Detection And Ranging (LiDAR) data; to calculate the spatial variability of load and photovoltaics energy supply, and thus to distinguish zones with various levels of energy self-sufficiency; and finally, to scrutinise the economic and environmental aspects of such a solution in given conditions. Wroclaw, the capital city of the Lower Silesia voivodeship in south-west Poland (Central Europe), was selected as a case study. The city has a population of close to 650,000 and an annual electricity consumption slightly exceeding 2.2 TWh. Industry constitutes 46% of that demand, and households 31%. The results show that up to 850 MW p of rooftop PV can be installed in the city, which has the potential to reduce the electrical energy related emissions by almost 30% and simultaneously to increase the city's energy self-sufficiency. Although energy storage, in the form of batteries, slightly improves both the autarky and environmental indices, the relation between potential PV generation and load makes them very infrequently useful (mostly in summer) and not economically justified. 

  • 227.
    Kalai, D. Y.
    et al.
    University of Stavanger, Stavanger, Norway.
    Stangeland, K.
    University of Stavanger, Stavanger, Norway.
    Li, Hailong
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Yu, Z.
    University of Stavanger, Stavanger, Norway.
    The effect of la on the hydrotalcite derived Ni catalysts for dry reforming of methane2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 3721-3726Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A series of 20Ni-Mg-Al hydrotalcite-like (HT) precursors were prepared to study the influence of lanthanum (La) on the catalytic activity of the catalysts in the dry reforming of methane (DRM). The catalysts were characterized by N2 adsorption-desorption, X-ray diffraction (XRD) and temperature-programmed reduction (TPR). All catalysts presented ordered mesoporous structures with a large specific surface area. XRD confirmed the presence of HT structure for all of the precursors while the La promotion resulted in an additional phase of Lanthanum carbonate hydroxide. TPR study showed larger reduction degree for the catalysts but also reduction peaks that are shifted to higher temperatures. DRM reactions at 600 and 750°C revealed that the DRM activity was increased by the addition of La, while the stability of the catalysts was reduced at 600°C. 

  • 228.
    Karim, Adel
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Bard, Gert
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Lindberg, E.
    Broman, L.
    Nordlander, S.
    Modeling of a Thermo-photovoltaic System (TPV)2007Ingår i: IGEC III Conf, 2007Konferensbidrag (Refereegranskat)
  • 229.
    Karimpourian, B.
    et al.
    Mälardalens högskola, Institutionen för samhällsteknik.
    Mahmoudi, J.
    Mälardalens högskola, Institutionen för samhällsteknik. Outokumpu, Sweden.
    Some important considerations in heatsink design2004Ingår i: Proceedings of the 6th International Conference on Thermal, Mechanical and Multi-Physics Simulation and Experiments in Micro-Electronics and Micro-Systems - EuroSimE 2005, 2004, s. 406-413Konferensbidrag (Refereegranskat)
    Abstract [en]

    This work is the study of heatsinks in theoretical and technical aspects. The objective of this paper is to provide a more clear imagine of heatsinks function and technology for beginners, designers, and researcher in various features. This paper serves as a guide for them to compare novel heatsink technologies. Theoretical correlations and simple equations recommended to calculate the heat transfer rate include Nusselt number, heat transfer coefficient and associated variables for some types of heatsinks to a certain extent are involved. Common terms and phenomenon in the heatsinks are defined.

  • 230.
    Karimpourian, Bijan
    Mälardalens högskola, Institutionen för samhällsteknik.
    cfd modelling and experimental study on the fluid flow and heat transfer in copper heat sink design2007Licentiatavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Abstract

    This thesis is studying the heatsinks new designs for copper heatsinks which utilizes modelling and simulation by CFD, construction of prototypes and experimental works. Challenges and complications in manufacturing of copper heatsinks are expressed and finding the solutions to these hindrances involve in this work. Numerical efforts supported by fluent are made to promote investigation and approaching the goal in which serves the new opportunities for wider application of copper material in heat sinks.

    However the thermal conductivity of copper is about double as aluminium but still aluminium heatsinks are commonly used for heat dissipation in computers.

    Comparing of heat performance of two analogous heatsink of different materials, aluminium and copper, is conducted by numerical analysis in the CFD environment.

    In addition to larger surface area and airflow velocity another solution for enhancement of heat dissipation is suggested.

    Manufacturing solutions of copper heatsinks are proposed which will facilitate fabrication of more high performance copper heatsinks than the current heavy and expensive models.

    Our first copper heat sink model is designed exclusively based on the technical observations and analyses of numerical simulation of two identical copper and aluminium heatsinks by CFD and as well as manufacturability concerns.

    This heat sink is fabricated mechanically and is tested by a number of heat sources and high sensitive devices such as adhesive K type thermocouple, data acquisition 34970A in associated with HP Bench Link program.

    An extent experimental work on aluminium heatsinks, integrated with forced convection, is performed in order to measure their thermal capacities.

    Comparison of the heat performance of a typical aluminium heatsink, which was the best among the all aluminium heat sinks and proposed copper heatsink under identical experimental conditions, is performed.

    Also in some numerical efforts, optimizing and predicting of the thermal characterization of the proposed heatsink with inclined free fins is developed. The model is scaled up in the fluent environment to predict its application in the cooling of larger heat generated electronic devices.

    Impingement air-cooling mode of force-convection is adopted for heat dissipation from high power electronic devices in associated with the proposed inclined fin model.

    Components of airflow velocity in the hollow spaces of the heatsink are discussed. Pressure drop and other thermal variables are analyzed analytical and by CFD code.

    Another mechanical manufactured copper heat sink is investigated. A new design of the base and fins is optimized.

    A three-dimensional finite volume method is developed to determine the performance of the proposed heatsink.

    Thermal and hydraulic characterization of the heat sink under air-forced convection cooling condition is studied. The flow behavior around the fins and some other parts of the heat sink is analyzed by utilizing CFD code.

    The hydraulic parameters including velocity profiles, distribution of static pressure, dynamic pressure, boundary layer and fluid temperature between the fins and in the passageway at the middle of the heat sink are analyzed and presented schematically.

    Furthermore the thermal characteristic of the proposed heatsink is studied by contouring the three dimensional temperature distributions through the fins and temperature of the heat source by CFD code.

  • 231.
    Karlsson, C
    et al.
    Mälardalens högskola, Institutionen för samhällsteknik.
    Dahlquist, Erik
    Mälardalens högskola, Institutionen för samhällsteknik.
    Dotzauer, Erik
    Mälardalens högskola, Institutionen för samhällsteknik.
    Data Reconciliation and Gross Error Detaction for Flue Gas Train in Heat and Power Plant, USAManuskript (Övrigt vetenskapligt)
  • 232.
    Karlsson, Christer
    et al.
    Mälardalens högskola, Institutionen för samhällsteknik.
    Dahlquist, Erik
    Mälardalens högskola, Institutionen för samhällsteknik.
    Process and sensor diagnostics: Data reconciliation for a flue gas channel2003Rapport (Övrigt vetenskapligt)
  • 233.
    Karlsson, Christer
    et al.
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Kvarnström, Andreas
    Dotzauer, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Estimation of process model parameters and process measurements – a heat exchanger example2006Ingår i: Conference Proceedings New Trends in Automation, 2006Konferensbidrag (Refereegranskat)
  • 234.
    Kavvalos, Mavroudis
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Compressor Characteristics for Transient and Part-load Performance Simulation2019Ingår i: Proceedings of the ASME Turbo Expo, American Society of Mechanical Engineers (ASME), 2019, American Society of Mechanical Engineers (ASME) , 2019Konferensbidrag (Refereegranskat)
    Abstract [en]

    Compressor performance tests are mainly focused on the typical range of operation, resulting in limited knowledge of compressor behavior in the low-speed region. The main target of this work comprises the generation of compressor characteristics at low part-load by giving particular insight into the physical aspect of this operating condition. It is necessary for running transient and part-load performance simulation and can be considered as the first crucial step toward an optimal engine starting schedule. Modelling the low part-load operating regime requires accurate component performance maps extended to the low-speed area, where engine starting and altitude relight occur. In this work, a robust methodology for generating compressor maps in the low part-load operating regime is developed. Compressor geometry and typical operation range compressor map are required as inputs. Two different modelling processes are incorporated within this methodology. Extrapolation based on the principle of similarity laws with modified law exponents constitutes the first modelling process, which seems inaccurate when predicting compressor performance at fixed-rotor conditions. Interpolation based on the fixed-rotor characteristic constitutes the second modelling process, which can be either linear or adaptive. The adaptive interpolation scheme was developed by the authors and generates low-speed characteristics using the same allocation trend as the one obtained from given performance data. It is observed that performance data points of each β-line follow an exponential trend in mass flow differences while increasing rotational speed, with a calculated average relativized Root Mean Square (RMS) error of less than 5%. Adapting the same trend in mass flow to the low-speed region, a compressor performance map with continuous exponential trend in all characteristics (for part- and full-load conditions) can be achieved. Implementing the developed methodology on the High Pressure Compressor (HPC) of the Energy Efficient Engine (E3) project is also presented, showcasing its applicability and the merit of it being incorporated into any conventional performance prediction tool. Furthermore, a sensitivity analysis for input variables, namely compressor exit effective area and pressure loss model coefficients is carried out, demonstrating the significant impact of the former on the shape of the low part-load characteristics. Generation of compressor characteristics at low-speeds with this methodology can be viewed as an enabler for running credible transient starting simulation and transient diagnostics, thereby defining an optimal starting schedule, applicable to both power generation and aerospace industry.

  • 235.
    Khanna, Yash
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Conceptual design and development of thermal management system for hybrid electric aircraft engine.: A study to develop a physical model and investigate the use of Mobil Jet Oil II as coolant for aircraft electrical propulsion under different scenarios and time horizons.2019Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
    Abstract [en]

    The ever-increasing levels of greenhouse gas emissions has led to the scientific community starting to explore the viability of electrical aircraft system, with the most prominent research and product development for hybrid electric system, which forms the transition phase from combustion to fully electric aircrafts. The primary objective of this thesis is to find solutions towards thermal management of the electrical components of a hybrid electric aircraft propulsion system, which generate a significant amount of heat while operating at heavy load conditions required to propel an aircraft. In view of these objectives a micro channel cold plate liquid cooling system, has been dynamically modelled using a combination of lumped parameter and thermal resistance methods of heat transfer analysis. The study investigates the prospects of using Mobil Jet Oil II, typically used as an aircraft lubricant as a coolant for the thermal management system. The primary components of this model are lithium ion battery, DC-AC inverter, permanent magnet motor, cross flow finned micro channel heat exchanger, centrifugal pump and ducts. The electrical components have been dimensioned according to energy storage and load requirements considering their efficiencies and gravimetric power/energy. The system has been simulated and analyzed under different scenarios considering the coolant inlet temperature, air temperature across the heat exchanger and on two-time horizons. Analysis has been done to study the dynamic trends of the component temperature and the coolant at different stages of the system. The scope of the study includes an evaluation of the added weight of the thermal management system under different time horizons and their comparison with results from a reference study. From the simulation results it can be concluded that Mobil Jet Oil II is a promising option as a coolant and therefore its use as a common fluid for gas turbine lubrication and as coolant, will benefit the aircraft as now no extra coolant reservoir is required, allowing reduction in weight carried by the aircraft.

  • 236.
    Kinell, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Energikartläggning i byggnader: Utredning av två byggnaders skillnad i energianvändning2019Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [en]

    When analyzing its property portfolio, the property manager Castellum AB noticed that the energy use of buildings with relatively large similarities could differ. In this case it concerned properties Bodarna 8 and Ölstånkan 14 in Örebro. The purpose of this work was to find out what the difference is due to and whether it was possible to reduce the difference with profitable energy efficiency measures. To solve this, previous studies concerning local buildings and handbooks on energy surveys and energy efficiency was studied. Then, an equation based on methods for determining energy use according to the legal requirements was constructed in Excel. And finally, models to calculate the profitability of the measures were created. The result showed differences in how the buildings are designed with different materials and how they are located, which probably affects the transmission losses of the buildings in different ways. Operation settings of the energy systems also contributed to the energy difference. Finally, it was noted that the buildings were below the average of 211 kWh/m2 within enclosing structural parts and year, for buildings in the same category. Ölstånkan nevertheless had a specific energy use, 116 kWh/m2, Atemp and year, that exceeded Bodarnas use of 86 kWh/m2, Atemp and year where energy for heating and estate electricity stood out. However, with proposed measures, it is possible to lower the specific energy of Ölstånkan to 65 kWh/m2, Atemp and year from 116 kWh/m2, Atemp and year while at the same time gaining profitability. 

  • 237.
    Kladovasilakis, Nikolaos
    et al.
    Aristotle Univ Of Thessaloniki, Greece.
    Efstathiadis, Theofilos
    Aristotle Univ Of Thessaloniki.
    Aslanidou, Ioanna
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Kalfas, Anestis
    Aristotle Univ Of Thessaloniki.
    Rotor Blade Design of an Axial Turbine using Non-Ideal Gases with Low Real-Flow Effects2017Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 142, s. 1127-1132Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study aims to describe a design methodology for supersonic rotor blade geometry, depending on the working fluid, for a low enthalpy Organic Rankine Cycle (ORC) system. Thus, the working fluid is a non-ideal gas with low impact of real flow effects. An innovate algorithm was developed, in order to generate the two-dimensional geometry of the rotor blade, for various working media. A design method, based on the principle of vortex flow field, was used for the blading design and, for the design of supersonic blades, the method of characteristics was selected as the most optimum. The geometry was tested using a commercial simulation software that uses a pressure-based solving algorithm named SIMPLE (Semi-implicit Method for Pressure-Linked Equations). Key advantages of this procedure are both its simplicity and precision of the results.

    The above procedure was applied for three working fluids, indicatively isobutane (R-600a), tetrafluroethane (R134a) and a mixture of 15% isobutane – 85% isopentane. Considering the ratio of specific heat capacities as constant, which is a realistic assumption for the operating conditions of these systems, the algorithm produces three different blade geometries. Results comparison indicates that every working fluid, for the same operating conditions and for the same design options, has a significantly differentiated geometry of the two-dimensional blade. Finally, the calculated total to total isentropic efficiency, for these rotor blades, is almost 92%. 

  • 238.
    Klintenberg, Patrik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Jamieson, M.
    Tranås Utbildningscentrum, Sweden .
    Kinyaga, V.
    Desert Research Foundation of Namibia, Namibia.
    Odlare, Monica
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Assessing biogas potential of slaughter waste: Can biogas production solve a serious waste problem at abattoirs?2014Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 61, s. 2600-2603Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Management of solid waste and wastewater in Namibia is a growing concern. This study investigated the biogas potential of slaughter waste at a small stock abattoir in southern Namibia. Laboratory experiments with five different mixes of blood; stomach content and manure from sheep were tested. Preliminary findings suggest that the most optimum mixture of slaughter waste was relatively large amounts of stomach and intestine content. The blood proportion should be kept relatively low, since the high nitrogen contents in the blood may inhibit the biogas production. The substrate mixture reflecting the actual ratio of waste generated in the slaughter process resulted in the highest methane production. This suggests that it is possible to produce viable amounts of biogas only using the waste produced at the abattoir, without adding other green substrate. Findings presented here together with results from a larger biogas digester, will be elaborated in the full paper.

  • 239.
    Klintenberg, Patrik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Lindmark, Johan
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Eskelinen, Tuomo
    Huopana, Tuomas
    Jääskeläinen, Ari
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    INVESTMENT MEMO ABOWE PILOT B SWEDEN2014Rapport (Refereegranskat)
    Abstract [en]

    This report is one output of ABOWE project (Implementing Advanced Concepts for Biological Utilization of Waste), which belongs to EU Baltic Sea Region Programme 2007-2013. ABOWE works with two promising technologies to unlock investments. Two mobile pilot plants have been built and will be tested in several Baltic Sea regions. These pilots are based on a novel biorefinery concept from Finnoflag Oy, Finland, known as Pilot A as well as a German dry fermentation process, known as Pilot B. The pilots form the basis for compilation of Investment Memos and organizing Investor Events. Also a regional model is used to evaluate the new processes’ economic and climatic impacts in each region. The desired outcome from ABOWE is implementer/investor driven continuation projects targeting full-scaleplant investments of the two technologies.

    The purpose of ABOWE Work Package 2 is to gather and communicate information from many aspects of technologies which are piloted with Pilot A and Pilot B to support investment decisions for full scale plants. In practice, a demo full scaleplant would be needed in order to convince the commercial investors and implementers to full scale plants. This means that ABOWE provides with profound information and a step forward regarding the two technologies. After ABOWE, the technology will need development for full-scale, and the feasibility will need further analysis. An implementer and investor should be found to conduct development further towards full-scale demo plant.

  • 240.
    Klintenberg, Patrik
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Thorin, Eva
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Lindmark, Johan
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Eskelinen, Tuomo
    Lappi, Mervi
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    Kauppinen, Marja
    Huopana, Tuomas
    Jääskeläinen, Ari
    Savonia University of Applied Sciences, University of Eastern Finland, Finland.
    Hakalehto, Elias
    INVESTMENT MEMO ABOWE PILOT A SWEDEN2015Rapport (Refereegranskat)
    Abstract [en]

    This report was compiled by the ABOWE project (Implementing Advanced Concepts for Biological Utilization of Waste) funded by the EU Baltic Sea Region Programme 2007-2013. This report presentsresults and information of relevance for the up-scaling of the Finnoflag biorefinery technology, piloted in Finland, Poland and Sweden, to support investment decisions towards full-scale implementation.

    The piloting of the technology done by the ABOWE project provides valuable information and a step forward regarding the technology. The next step, after the pilot phase, would be to construct a full-scalede monstration plant to showcase the potential of the technology to potential commercial investorsor implementers. The bioprocess will need to be further designedand optimized through longer testing with selected waste materials to produce targeted products. This will all0w for full-scaleoperationsand further feasibility analysis. This falls beyond the scope of the ABOWE project. This report forms the basis of an investment memo that provides decision support topossible implementers and investors that are interested in taking the lead in the development of the technology further to a full-scale demo plant.

  • 241.
    Kos, Cristoffer
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Hermansson, Kristoffer
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    BUILDING AND SIMULATING DYNAMIC MODELS OF DISTRICT HEATING NETWORKS WITH MODELICA: Using Matlab to process data and automate modelling and simulation2017Självständigt arbete på avancerad nivå (masterexamen), 300 hpStudentuppsats (Examensarbete)
    Abstract [en]

    District heating systems are common in Nordic countries today and accounts for a great portion of the heat demand. In Sweden, total district heating end use in the last years has been around 50 TWh and district heating accounts for roughly 50 % of the total heat demand. Suppliers of district heating must balance demand and supply, often in large and complex networks. Heat propagation can be in the range of hours and it is not known in detail how the heat will propagate during transient conditions. A dynamic model has been developed in OpenModelica and a method for modeling, handling data, simulating and visualizing the results of a district heating network was developed using Matlab as core. Data from Mälarenergi AB, a district heating producer and grid operator, was used for validation of the model. Validation shows that the model works well in predicting heat propagation and temperature distribution in the network and that the model can be scaled up to a large number of heat exchangers and pipes. The model is robust and can handle bi-directional and reversing flows in complex ring structures. It was concluded that OpenModelica together with Matlab is a good combination for creating models of district heating networks, as a high degree of standardization and automation can be achieved. This, together with visualization of the heat propagation, makes it useful for the understanding of the district heating network during transient conditions.

  • 242.
    Kovala, Tommy
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Industriell ekonomi och organisation.
    Wallin, Fredrik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Hallin, Anette
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Industriell ekonomi och organisation.
    Factors influencing industrial excess heat collaborations2016Ingår i: Energy Procedia, ISSN 1876-6102, E-ISSN 1876-6102, Vol. 88, s. 595-599Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In Sweden there is a potential to double the amount of industrial excess heat from todays 5 TWh that is delivered into district heating networks. This paper investigates factors that are influencing industrial excess heat collaborations. The paper presents result from qualitative interviews as well as answers through a more quantitative web based survey which has been sent out to stakeholders in existing Swedish industrial excess heat collaborations. This work provides new evidence on that economic motivations are the most common driver for starting up a collaboration, but well in place factors like transparency as well as investment sharing between the partners becomes important for a long-term successful collaboration.

  • 243.
    Kubilay, Kevser
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Kucska, Kelly
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Energi och ventilation vid biomassaproduktion av larver: Optimering av ett ventilationssystem med hjälp av beräkningsmodell i Excel för containern i demoanläggningen, i Lilla Nyby2018Självständigt arbete på grundnivå (kandidatexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    Matavfall som kommer in till Eskilstuna Strängnäs Energi & Miljö (ESEM), har mestadels använts till biogasproduktion. Eftersom ESEMs rötningspanna är liten har inte allt matavfall gjorts om till biogas, utan gått till förbränning i Västerås istället. För att underöka eventuella utvecklingsmöjligheter och förbättringsmöjligheter har ESEM gått ihop med Sveriges Lantbruksuniversitet (SLU). Där undersökning av matning med matavfall till afrikanska fluglarver pågick. Ifall detta projekt är praktiskt genomfört på företaget ESEM skulle två nya produkter i form av protein och jord, kunna säljas utöver biogas.

    I denna studie har det undersökts ifall det är möjligt att kunna mata fluglarverna med matavfall. Det ställs krav på rätt temperatur och luftflöde för utrymmet. Därmed har fokus till detta examensarbete varit att optimera en ventilationsmodell för systemet.

    För att utföra detta projekt krävdes data från tidigare studier, forskning och experiment, vilket skrevs in i behandlingsprogrammet Excel. Där ett idealt ventilationsflöde med verkningsgraden 50 %, till varje enskild behandlingslåda med fluglarver i olika levnadsstadier, på 1,56 m3/h (en låda) togs fram med hjälp av tidigare studier.

    Fluglarverna är planerade att bli placerade i brödlådor med tillhörande ställningar i en container och varje låda ska både ha fluglarver och matavfall. Undersökningen för detta examensarbete var att bestämma hur ställningarna med behandlingslådor ska placeras i containern. Genom att välja den kombination av behandlingslådorna, som är mest optimerad och praktiskt genomförbar. Det utfördes en simulering i Excel som redovisade andelen värme och förångning som varje behandlingslåda med stadie 1, 6 och 12 genererade. Simuleringar genomfördes för olika kombinationer och beräknade värmeutvecklingen från vardera behandlingslåda och kombination. Vilket resulterade i att det fanns två möjliga placeringar av behandlingslådorna i ställningarna, i containern.

    Den första placeringen i containern var planerad med att ställning 1 skulle ha behandlingslådor med larvstadiet/dag 1. Ställning 2 respektive 3 skulle ha behandlingslådor med larvstadiet/dag 6 respektive larvstadiet/dag 12. Det vill säga kombination 1 – 6 – 12. Vilket betyder att alla ställningarna i den kombinationen är seriekopplade med varandra. Medan varje enskild behandlingslåda i en ställning är parallellkopplade. Då denna kombination redovisar att ställning 3 med behandlingslådor av larvstadiet/dag 12, har högst andel förångning och värmegenerering. Denna placering ansågs rimlig att ställa lägst in i containern, närmast frånluftutloppet på container. Både av praktiska skäl och att undvika värmespridning som kan medföra kondens.

    Den andra placeringen i containern var tänkt att ställning 1 skulle ha behandlingslådor med larvstadiet/dag 12. Ställning 2 respektive 3 skulle ha behandlingslådor med larvstadiet/dag 6 respektive larvstadiet/dag 1. Det vill säga kombination 12 – 6 – 1. Vilket betyder att alla ställningarna i den kombinationen är seriekopplade med varandra. Medan varje enskild behandlingslåda i en ställning är parallellkopplade. Denna kombination redovisar minst temperaturdifferens mellan ställningarna (mellan behandlingslådorna) och visade även möjligheten att utnyttja värmen i behandlingslådorna från tidigare lådor. Genom att luften som förs vidare från larvstadiet/dag 12 till larvstadiet/dag 6, värmer då upp avfallsaktiviteten.

    Studien resulterade i att det optimala luftflödet med verkningsgraden 50 %, var 1,56 m3/h. Energibalanserna utfördes i beräkningsmodellen med hänsyn till luftflödet in och ut ur en behandlingslåda. Avfallstemperaturen som bestämdes vara ideal vid 30°C i detta examensarbete är en betydelsefull parameter för resultatet. Resultatet optimerades med hänsyn till att en avfallstemperatur på 30°C skulle bibehållas genom beräkningarna. Den optimala kombinationen bestämdes vara kombination av de tre behandlingslådorna 1 – 6 – 12, där medeltemperaturen på avfallet var 30,22°C. Denna kombination diskuterades även vara den mest praktiskt hanterbara, i containern hos ESEM. Vid hänsyn till kondensering som tidigare examensarbeten diskuterat är kombination 12 – 6 – 1 ett alternativ. De sex kombinationerna resulterar inte i stora temperaturdifferenser som kan orsaka kondensering. Ifall hänsyn tas till kondensering är alternativet 12 – 6 – 1 bäst. Då avfallstemperaturen är stabil jämfört med de fem andra kombinationerna.

    Ett helt slutet system med tre seriekopplade ställningar som innehåller tre parallellkopplade behandlingslådor erhålls resultat från två fall. Sommarfallet med en temperatur på 20°C resulterade i högre avfallstemperaturen jämfört med vinterfallet på 10°C. Däremot är avfallstemperaturen under den maximala gränsen, det vill säga är avfallstemperaturen på en behaglig nivå för larvproduktionen.

    Resultaten erhållna från detta examensarbete redovisar att det är teoretiskt och praktiskt möjligt att utföra en nedbrytningsprocess med hjälp av larver. Matavfallet bryts ner och bidrar med en ny produkt, näringsrik jord, samtidigt som den underlättar för ESEM nedbrytningsprocess.

  • 244.
    Kuivamäki, Daniel
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Mohseni, Mohammad
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Värme- och massflöde i precisionsgjuteri: Optimering och undersökning av simuleringsparametrar för precisionsgjutning2019Självständigt arbete på grundnivå (yrkesexamen), 10 poäng / 15 hpStudentuppsats (Examensarbete)
    Abstract [sv]

    För att kunna prediktera fel under processen precisionsgjutning, används simulering som ett verktyg att bestämma hur detaljer skall gjutas. Det finns flertalet parametrar som är möjliga att manipulera eller ändra. För att komma så nära ett verkligt scenario som möjligt behöver dessa parametrar optimeras mot verkligheten. Syftet med detta arbete är att analysera faktorer som påverkar värmeöverföring för att sedan presentera optimeringsförslag åt TPC Components AB mot de gjorda mätningarna. Detta görs för att kunna förutsäga till exempel hur snabbt ett föremål kyls i processen och hur det påverkar det slutgiltiga resultatet. Resultat från de optimerade simuleringarna jämförs mot ett praktiskt försök och även TPC Components tidigare standard utvärderas mot arbetets optimerade simuleringar.

    En viktig fråga är att undersöka varför simuleringsprogrammet inte blir identiskt med verkligheten och hur detta undersöks. Känslighetsanalyser utgör därmed en stor del av arbetet och det är av vikt att undersöka enskilda parametrar för att få en uppfattning om vad som påverkar resultatet och vad som går att bortse från.

    Resultatet av arbetet visar att ändrade parametrar för indata vid precisionsgjutning i TPC Components AB:s vakuumprocess har resulterat i en mer pålitlig simulering. Simuleringen bygger nu på vetenskapliga bevis och faktiska uppmätningar under processen för att kunna simulera så likt verkligheten som möjligt. Arbetet resulterar i att färre gjutförsök innan godkänt tillvägagångssätt för nya detaljer behövs, då simulering kommer att visa resultat närmare verkligheten.

    Arbetet har förbättrat TPC Components simuleringsarbete vilket kommer påverka både arbetstid, kostnader och miljö på ett positivt sätt.

  • 245.
    Kullman, M.
    et al.
    Eskilstuna Strängnäs Energy and Environment, Stockholm, Sweden.
    Campillo, Javier
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Fertner, C.
    University of Copenhagen, Department of Geosciences and Natural Resource Management, Copenhagen, Denmark.
    Giffinger, R.
    Vienna University of Technology, Department of Spatial Planning, Vienna, Austria.
    Grosse, J.
    University of Copenhagen, Department of Geosciences and Natural Resource Management, Copenhagen, Denmark.
    Groth, N. B.
    University of Copenhagen, Department of Geosciences and Natural Resource Management, Copenhagen, Denmark.
    Haindlmaier, G.
    Vienna University of Technology, Department of Spatial Planning, Vienna, Austria.
    Kunnasvirta, A.
    Turku University of Applied Sciences, Environment and Business, Turku, Finland.
    Strohmayer, F.
    Vienna University of Technology, Department of Spatial Planning, Vienna, Austria.
    Haselberger, J.
    Hamburg University of Applied Sciences, Hamburg, Germany.
    Note: The PLEEC project–planning for energy efficient cities2016Ingår i: Journal of Settlements and Spatial Planning, ISSN 2069-3419, Vol. 2016, nr Special Issue: 5, s. 89-92Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Globally, more than 50% of all people are living in cities today. Enhancing sustainability and efficiency of urban energy systems is thus of high priority for global sustainable development. The European research project PLEEC (Planning for Energy Efficient Cities) focuses on technological, innovative, behavioural and structural capacities of European medium-sized cities in their transition towards Energy Smart Cities. The variation of strengths and weaknesses of cities’ capabilities as well as practices and tools for enhancing energy efficient performance of urban energy systems were at the centre of the project. This short note summarises its main findings.

  • 246.
    Kumlin, Jesper
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Industriell ekonomi och organisation.
    True operation simulation for urban rail: Energy efficiency from access to Big data2019Självständigt arbete på avancerad nivå (yrkesexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 247.
    Kumm, Mia
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Carried Fire Load in Mass Transport Systems: – a study of occurrence, allocation and fire behavior of bags and luggage in metro and commuter trains in Stockholm2010Rapport (Övrigt vetenskapligt)
    Abstract [en]

    A fire in an underground mass transport system is a great challenge for the fire and rescue services. The outcome of both the evacuation and the fire and rescue operation is dependent of the fire behavior. The fire load will influence the duration of the fire and the possible damage on the construction. It will also affect the fire and rescue services possibilities and need to extinguish the fire.  When designing new trains high fire safety requirements are raised on the carriage, the interior and the used material. The fire accidents in the Baku Metro in 1995 and in the funicular railway in the Kaprun tunnel in 2000 shows that the carried fire load also has a great impact of the fire. In this report  the carried fire load in the Baku and Kaprun fires are discussed and the occurrence and location of carried fire load in the Stockholm mass transport systems is described. Based on the field study in Stockholm typical bags and luggage have been chosen and fire test have been performed at SP Technical Research Institute of Sweden. The test includes different sizes of bags and luggage with representative contents as well as prams and shopping bags.

  • 248.
    Kumm, Mia
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Rescue operations during construction of tunnels: -a study of the fire and rescue services possibilities and their interaction with the tunnel contractor2010Rapport (Övrigt vetenskapligt)
    Abstract [en]

    The last decades a number of successful research projects have been performed in Europe and in the rest of the world regarding fire in tunnels. The project mainly deals the conditions for newly built or already existing tunnels. During the construction phase most of the fire technical installations designed for the ready tunnel not yet are in operation, the evacuation and response routes can be very long and the fire load essentially different from the ready tunnel. This report describes the basic problems with rescue operations in tunnels and discusses the possibilities and limitations for rescue operations during construction. Examples are given for chosen type tunnels and recommendations are given. The Swedish national legislation is analyzed and discussed. Finally recommendations for the contingency planning and the interaction between the fire- and rescue services and the tunnel contractor are made.

  • 249.
    Kumm, Mia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Palm, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Storstockholms brandförsvar .
    Palmkvist, Krister
    Södra Älvsborgs Räddningstjänstförbund.
    Lönnermark, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Ingason, Haukur
    SP Sveriges Tekniska Forskningsinstitut.
    Räddningsinsats i tunnelmiljö: Fullskaleförsök i Tistbrottet, Sala2014Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    I oktober 2013 genomfördes sex fullskaliga brandförsök med kombinerat förflyttnings och släckmoment i Björka Minerals dolomitgruva i Tisbrottet i Sala. Tidigare har dessa två moment inte kombinerats under kontrollerade former där mätningar och observationer dokumenterats i så omfattande grad som i denna försöksserie. Rökdykarnas uppgift vid samtliga av försöken var att avancera in i tunneln och släcka branden. De sex olika försöken utgjordes av konventionell slangutläggning med slangkorgar respektive bärsele, utlägg med tomt system fram till brandplatsen, CAFS, skärsläckare och konventionell slangutläggning med hjälp av materielvagn och depåluft. Försöken visade att konventionell slangutläggning tar lång tid i anspråk, men att utlägg med tomt system och bärsele kan korta tiderna och minska belastningen. Försöken visade också att system med lägre vattenflöden hade möjligheter att slå ner branden, men att mängden vatten var avgörande för att undvika återantändning. Värmekameror är generellt inte anpassade för tunnelmiljöer och ett stort behov finns för vidare utveckling av både utrustning och utbildningsmaterial.

  • 250.
    Kumm, Mia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Palmkvist, Krister
    Södra Älvsborgs Räddningstjänstförbund, Sweden.
    Palm, Anders
    Storstockholms brandförsvar, Sweden.
    Värmekamera vid brand under mark: Ett utbildningsmaterial för räddningstjänsten2014Rapport (Övrigt vetenskapligt)
    Abstract [sv]

    Rapporten är framtagen inom ramen för det MSB-finansierade projektet TMU – Taktik och metodik vid brand under mark – och avsedd att användas som ett utbildningsmaterial för räddningstjänsten. Utbildningsmaterialet förutsätter viss grundläggande kunskap om användning av värmekamera vid brand, men kräver ingen tidigare erfarenhet av användning i undermarksmiljö. Rapporten innehåller såväl teoretiska delar som praktiska övningsexempel. Områden som behandlas är användning vid orientering och förflyttning, bedömning av brand, brandgasspridning och värmetransport samt riskbedömning för rökdykarens säkerhet.

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