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  • 201.
    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.

  • 202.
    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)
  • 203.
    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.

  • 204.
    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.

  • 205.
    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.

  • 206.
    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.

  • 207.
    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.

  • 208.
    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)
  • 209. 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)
  • 210.
    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.

  • 211.
    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. 

  • 212.
    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)
  • 213.
    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)
  • 214.
    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.

  • 215.
    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. 

  • 216.
    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)
  • 217.
    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.

  • 218.
    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.

  • 219.
    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)
  • 220.
    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)
  • 221.
    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)
  • 222.
    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. 

  • 223.
    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%. 

  • 224.
    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.

  • 225.
    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.

  • 226.
    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.

  • 227.
    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.

  • 228.
    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.

  • 229.
    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.

  • 230.
    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.

  • 231.
    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, 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.

  • 232.
    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)
  • 233.
    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.

  • 234.
    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.

  • 235.
    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.

  • 236.
    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.

  • 237.
    Kumm, Mia
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Söderström, Jenny
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik.
    Lönnermark, Anders
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik. SP Sveriges Tekniska Forskningsinstitut.
    EPS insulated façade fires from a fire and rescue perspective2013Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper highlights the challenges the fire and rescue services can meet at façade fires involving EPS insulation during construction and use of a building. The EPS characteristics are discussed in respect to the fire and rescue operation and results from orientating fire tests performed at a fire and rescue services training and test field are presented. Types of evacuation solutions, involving the fire and rescue services, where façade fires can delay or completely rule out the possibilities for safe evacuation, are presented. The restrictions in the Swedish building codes regarding use of combustible insulation are analysed and reflections over the practical problems with following the instructions to keep an EPS insulated façade safe through the building’s whole lifespan are made. A number of occurred fires involving EPS are discussed and analysed from a fire and rescue perspective. Finally, recommendations are given for the fire and rescue services and future research fields are proposed.

  • 238. Kvarnström, Johan
    et al.
    Liljedahl, Jakob
    Dotzauer, Erik
    Mälardalens högskola, Akademin för hållbar samhälls- och teknikutveckling.
    Forward temperatures and production planning in district heating systems2006Ingår i: The 10th International Symposium on District Heating and Cooling, 2006Konferensbidrag (Refereegranskat)
  • 239.
    Kyprianidis, Konstantinos
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Cranfield University.
    Camilleri, William
    Cranfield University, Cranfield, UK.
    Gas Turbines for Power and Propulsion2015Ingår i: Handbook of Clean Energy Systems: Volume 2 - Clean Energy Conversion Technologies / [ed] Jinyue Yan, Chichester, West Sussex, UK: John Wiley & Sons, 2015, 1, s. 1-25Kapitel i bok, del av antologi (Refereegranskat)
    Abstract [en]

    For over seven decades, the gas turbine has been used successfully in a variety of applications including aircraft, ship, and surface vehicle propulsion as well as for electrical power and heat generation. The gas turbine is in essence a type of internal combustion engine comprising in its simplest form a compressor, a combustor, and a turbine. It can utilize a variety of different fuels, most commonly natural gas and kerosene (Jet-A).

    The gas turbine has played a key role in the expansion of jet transportation and is currently the prime mover for almost all commercial applications, other than light aircraft. It also has had a considerable impact in the power generation sector with efficiencies in excess of 40% for simple cycles, and close to 60% for combined cycles. Over the next decades, it is expected that the gas turbine will continue to play a significant role in the power generation and propulsion market.

    This article covers the fundamentals of gas turbine design, performance, and future technology development. First, a short presentation of the fundamental thermodynamics relating to the gas turbine is given. It is followed by an ideal analysis of three major cycles: the simple cycle, the intercooled cycle, and the intercooled recuperated cycle. Typical losses for gas turbine components are discussed along with relevant performance modeling methods. The fundamental principles of gas turbine conceptual design are presented followed by an assessment of the real performance of the three major cycles. Finally, a critical review is presented of future gas turbine concepts and their enabling technologies, with the primary focus on civil aircraft propulsion. Recent development trends and the primary research and development efforts by major gas turbine manufacturers are discussed in detail.

  • 240.
    Kyprianidis, Konstantinos
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    Dahlquist, Erik
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi.
    On the trade-off between aviation NOx and energy efficiency2017Ingår i: Applied Energy, ISSN 0306-2619, E-ISSN 1872-9118, Vol. 185, s. 1506-1516Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This study aims to assess the trade-off between the ever-increasing energy efficiency of modern aero-engines and their   performance. The work builds on performance models previously developed to optimise the specific fuel consumption of future aero-engine designs. As part of the present work a simple and adaptable   emissions correlation for Rich-burn Quick-quench Lean-burn combustor designs is derived. The proposed model is computationally inexpensive and sufficiently accurate for use in aero-engine multi-disciplinary conceptual design tools. Furthermore, it is possible to adapt the correlation to model the   emissions of combustors designed for very aggressive future cycles. An approach to lean-burn combustor   emissions modelling is also presented. The simulation results show that improving engine propulsive efficiency is likely to have a benign effect on  emissions at high altitude; at sea-level conditions   emissions are particularly likely to reduce. Improving engine thermal efficiency however has a detrimental effect on   emissions from RQL combustors, both at high altitude and particularly at sea-level conditions. LDI combustor technology does not demonstrate such behaviour. Current legislation permits trading   emissions engine efficiency and hence reduce   emissions. If we are to reduce the contribution of aviation to global warming, however, future certification legislation may need to become more stringent and comprehensive.

  • 241.
    Kyprianidis, Konstantinos G.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik. Cranfield University.
    Dynamic Simulation of Aircraft Propulsion Systems2006Självständigt arbete på avancerad nivå (masterexamen), 20 poäng / 30 hpStudentuppsats (Examensarbete)
  • 242.
    Kyprianidis, Konstantinos G.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Cranfield University.
    Future Aero Engine Designs: An Evolving Vision2011Ingår i: Advances in Gas Turbine Technology / [ed] Ernesto Benini, Rijeka, Croatia: InTech, 2011, 1st, s. 3-24Kapitel i bok, del av antologi (Övrigt vetenskapligt)
  • 243.
    Kyprianidis, Konstantinos G.
    Cranfield University, UK.
    Multi-Disciplinary Conceptual Design of Future Jet Engine Systems2010Doktorsavhandling, monografi (Övrigt vetenskapligt)
    Abstract [en]

    This thesis describes various aspects of the development of a multi-disciplinary aero engine conceptual design tool, TERA2020 (Techno-economic, Environmental and Risk Assessment for 2020), based on an explicit algorithm that considers: engine performance, engine aerodynamic and mechanical design, aircraft design and performance, emissions prediction and environmental impact, engine and airframe noise, and production, maintenance and direct operating costs.

    As part of this research effort, a newly-derived semi-empirical NOx correlation for modern rich-burn single-annular combustors is proposed. The development of a numerical methods library is also presented, including an improved gradient-based algorithm for solving non-linear equation systems. Common assumptions made in thermo-fluid modelling for gas turbines and their effect on caloric properties are investigated, while the impact of uncertainties on performance calculations and emissions predictions at aircraft system level is assessed. Furthermore, accuracy limitations in assessing novel engine core concepts as imposed by current practice in thermo-fluid modelling are identified.

    The TERA2020 tool is used for quantifying the potential benefits from novel technologies for three low pressure spool turbofan architectures.  The impact of failing to deliver specific component technologies is quantified, in terms of power plant noise and CO2 emissions. To address the need for higher engine thermal efficiency, TERA2020 is again utilised; benefits from the potential introduction of heat-exchanged cores in future aero engine designs are explored and a discussion on the main drivers that could support such initiatives is presented. Finally, an intercooled core and conventional core turbofan engine optimisation procedure using TERA2020 is presented. A back-to-back comparison between the two engine configurations is performed and fuel optimal designs for 2020 are proposed.

    Whilst the detailed publications and the work carried out by the author, in a collaborative effort with other project partners, is presented in the main body of this thesis, it is important to note that this work is supported by 20 conference and journal papers.

  • 244.
    Kyprianidis, Konstantinos G.
    et al.
    Cranfield University, Bedfordshire, England, UK.
    Colmenares Quintero, Ramon F.
    Cranfield University, Bedfordshire, England, UK.
    Pascovici, Daniele S.
    Cranfield University, Bedfordshire, England, UK.
    Ogaji, Stephen O. T.
    Cranfield University, Bedfordshire, England, UK.
    Pilidis, Pericles
    Cranfield University, Bedfordshire, England, UK.
    Kalfas, Anestis I.
    Aristotle University of Thessaloniki, Thessaloniki, Greece.
    EVA: A Tool for EnVironmental Assessment of Novel Propulsion Cycles2008Ingår i: ASME Turbo Expo 2008: Power for Land, Sea, and AirVolume 2: Controls, Diagnostics and Instrumentation; Cycle Innovations; Electric PowerBerlin, Germany, June 9–13, 2008, 2008, s. 547-556Konferensbidrag (Refereegranskat)
    Abstract [en]

    This paper presents the development of a tool for EnVironmental Assessment (EVA) of novel propulsion cycles implementing the Technoeconomical Environmental and Risk Analysis (TERA) approach. For nearly 3 decades emissions certification and legislation has been mainly focused on the landing and take-off cycle. Exhaust emissions measurements of NOx, CO and unburned hydrocarbons are taken at Sea Level Static (SLS) conditions for 4 different power settings (idle, descent, approach and take-off) and are consecutively used for calculating the total emissions during the ICAO landing and take-off cycle. With the global warming issue becoming ever more important, stringent emissions legislation is soon to follow, focusing on all flight phases of an aircraft. Unfortunately, emissions measurements at altitude are either extremely expensive, as in the case of altitude test facility measurements, or unrealistic, as in the case of direct in flight measurements. Compensating for these difficulties, various existing methods can be used to estimate emissions at altitude from ground measurements. Such methods, however, are of limited help when it comes to assessing novel propulsion cycles or existing engine configurations with no SLS measurements available. The authors are proposing a simple and fast method for the calculation of SLS emissions, mainly implementing ICAO exhaust emissions data, corrections for combustor inlet conditions and technology factors. With the SLS emissions estimated, existing methods may be implemented to calculate emissions at altitude. The tool developed couples emissions predictions and environmental models together with engine and aircraft performance models in order to estimate the total emissions and Global Warming Potential of novel engine designs during all flight phases (i.e. the whole flight cycle). The engine performance module stands in the center of all information exchange. In this study, EVA and the described emissions prediction methodology have been used for the preliminary design analysis of three spool high bypass ratio turbofan engines. The capability of EVA to radically explore the design space available in novel engine configurations, while accounting for fuel burn and global warming potential during the whole flight cycle of an aircraft, is illustrated.

  • 245.
    Kyprianidis, Konstantinos G.
    et al.
    Chalmers University of Technology, Sweden.
    Grönstedt, Tomas
    Chalmers University of Technology, Sweden.
    Barbosa, Joao R.
    Instituto Tecnológico de Aeronáutica - ITA, Sao Paolo, Brazil.
    Lessons Learned from the Development of Courses on Gas Turbine Multi-disciplinary Conceptual Design2012Ingår i: Proc. ASME. 44694; Volume 3: Cycle Innovations; Education; Electric Power; Fans and Blowers; Industrial and Cogeneration. GT2012-70095, 2012, s. 513-523Konferensbidrag (Refereegranskat)
    Abstract [en]

    Despite the need for highly qualified experts, multi-disciplinary gas turbine conceptual design has not been a common study topic in traditional post-graduate curriculums. Although many courses on specialised topics in gas turbine technology take place, limited attention is given on connecting these individual topics to the overall engine design process. Teaching conceptual design as part of a post-graduate curriculum, or as an intensive short course, may help to address the industrial need for engineers with early qualifications on the topic i.e., prior to starting their careers in the gas turbine industry.

    This paper presents details and lessons learned from: (i) the integration of different elements of conceptual design in an existing traditional MSc course on gas turbine technology through the introduction of group design tasks, and (ii) the development of an intensive course on gas turbine multi-disciplinary conceptual design as a result of an international cooperation between academia and industry.

    Within the latter course, the students were grouped in competing teams and were asked to produce their own gas turbine conceptual design proposals within a given set of functional requirements. The main concept behind the development of the new design tasks, and the new intensive course, has been to effectively mimic the dynamics of small conceptual design teams, as often encountered in industry. The results presented are very encouraging, in terms of enhancing student learning and developing engineering skills.

  • 246.
    Kyprianidis, Konstantinos G.
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Cranfield University.
    Sethi, Vishal
    Cranfield University.
    Ogaji, Stephen O. T.
    Cranfield University.
    Pilidis, Pericles
    Cranfield University.
    Singh, Riti
    Cranfield University.
    Kalfas, Anestis I.
    Aristotle University of Thessaloniki.
    Thermo-Fluid Modelling for Gas Turbines-Part I: Theoretical Foundation and Uncertainty Analysis2009Ingår i: ASME TURBO EXPO 2009 Proceedings, GT2009-60092, 2009Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this two-part publication, various aspects of thermo-fluidmodelling for gas turbines are described and their impact onperformance calculations and emissions predictions at aircraftsystem level is assessed. Accurate and reliable fluid modellingis essential for any gas turbine performance simulation softwareas it provides a robust foundation for building advanced multidisciplinarymodelling capabilities. Caloric properties forgeneric and semi-generic gas turbine performance simulationcodes can be calculated at various levels of fidelity; selection ofthe fidelity level is dependent upon the objectives of thesimulation and execution time constraints. However, rigorousfluid modelling may not necessarily improve performancesimulation accuracy unless all modelling assumptions andsources of uncertainty are aligned to the same level. Certainmodelling aspects such as the introduction of chemical kinetics,and dissociation effects, may reduce computational speed andthis is of significant importance for radical space explorationand novel propulsion cycle assessment.

    This paper describes and compares fluid models, based ondifferent levels of fidelity, which have been developed for anindustry standard gas turbine performance simulation code and an environmental assessment tool for novel propulsion cycles.The latter comprises the following modules: engineperformance, aircraft performance, emissions prediction, andenvironmental impact. The work presented aims to fill thecurrent literature gap by: (i) investigating the commonassumptions made in thermo-fluid modelling for gas turbinesand their effect on caloric properties and (ii) assessing theimpact of uncertainties on performance calculations andemissions predictions at aircraft system level.

    In Part I of this two-part publication, a comprehensiveanalysis of thermo-fluid modelling for gas turbines is presentedand the fluid models developed are discussed in detail.Common technical models, used for calculating caloricproperties, are compared while typical assumptions made influid modelling, and the uncertainties induced, are examined.Several analyses, which demonstrate the effects of composition,temperature and pressure on caloric properties of workingmediums for gas turbines, are presented. The working mediumsexamined include dry air and combustion products for variousfuels and H/C ratios. The errors induced by ignoringdissociation effects are also discussed.

  • 247.
    Kyprianidis, Konstantinos G.
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Cranfield University.
    Sethi, Vishal
    Cranfield University.
    Ogaji, Stephen O. T.
    Cranfield University.
    Pilidis, Pericles
    Cranfield University.
    Singh, Riti
    Cranfield University.
    Kalfas, Anestis I.
    Aristotle University of Thessaloniki.
    Thermo-Fluid Modelling for Gas Turbines-Part II: Impact on Performance Calculations and Emissions Predictions at Aircraft System Level2009Ingår i: ASME TURBO EXPO 2009 Proceedings, GT-2009-60101, 2009, s. 483-494Konferensbidrag (Refereegranskat)
    Abstract [en]

    In this two-part publication, various aspects of thermo-fluidmodelling for gas turbines are described and their impact onperformance calculations and emissions predictions at aircraftsystem level is assessed. Accurate and reliable fluid modellingis essential for any gas turbine performance simulation softwareas it provides a robust foundation for building advanced multidisciplinarymodelling capabilities. Caloric properties forgeneric and semi-generic gas turbine performance simulationcodes can be calculated at various levels of fidelity; selection ofthe fidelity level is dependent upon the objectives of thesimulation and execution time constraints. However, rigorousfluid modelling may not necessarily improve performancesimulation accuracy unless all modelling assumptions andsources of uncertainty are aligned to the same level. Certainmodelling aspects such as the introduction of chemical kinetics,and dissociation effects, may reduce computational speed andthis is of significant importance for radical space explorationand novel propulsion cycle assessment.

    This paper describes and compares fluid models, based ondifferent levels of fidelity, which have been developed for anindustry standard gas turbine performance simulation code and an environmental assessment tool for novel propulsion cycles.The latter comprises the following modules: engineperformance, aircraft performance, emissions prediction, andenvironmental impact. The work presented aims to fill thecurrent literature gap by: (i) investigating the commonassumptions made in thermo-fluid modelling for gas turbinesand their effect on caloric properties and (ii) assessing theimpact of uncertainties on performance calculations andemissions predictions at aircraft system level.

    In Part II of this two-part publication, the uncertaintyinduced in performance calculations by common technicalmodels, used for calculating caloric properties, is discussed atengine level. The errors induced by ignoring dissociation areexamined at 3 different levels: i) component level, ii) enginelevel, and iii) aircraft system level. Essentially, an attempt ismade to shed light on the trade-off between improving theaccuracy of a fluid model and the accuracy of a multidisciplinarysimulation at aircraft system level, againstcomputational time penalties. The results obtained demonstratethat accurate modelling of the working fluid is not alwaysessential; the accuracy/uncertainty for an overall engine modelwill always be better than the mean accuracy/uncertainty of the individual component estimates as long as systematic errors arecarefully examined and reduced to acceptable levels to ensureerror propagation does not cause significant discrepancies.Computational time penalties induced by improving theaccuracy of the fluid model as well as the validity of the idealgas assumption for future turbofan engines and novelpropulsion cycles are discussed.

  • 248.
    Kyprianidis, Konstantinos
    et al.
    Mälardalens högskola, Akademin för ekonomi, samhälle och teknik. Mälardalens högskola, Akademin för ekonomi, samhälle och teknik, Framtidens energi. Cranfield University, UK.
    Grönstedt, Tomas
    Chalmers University of Technology, Sweden.
    Barbosa, Joao R.
    Instituto Technológico de Aeronáutica, São José dos Campos, Brazil.
    Lessons Learned From the Development of Courses on Gas Turbine Multidisciplinary Conceptual Design2013Ingår i: Journal of engineering for gas turbines and power, ISSN 0742-4795, E-ISSN 1528-8919, Vol. 135, nr 7, s. Article number 072601-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Despite the need for highly qualified experts, multidisciplinary gas turbine conceptual design has not been a common study topic in traditional postgraduate curriculums. Although many courses on specialized topics in gas turbine technology take place, limited attention is given on connecting these individual topics to the overall engine design process. Teaching conceptual design as part of a postgraduate curriculum, or as an intensive short course, may help to address the industrial need for engineers with early qualifications on the topic, i.e., prior to starting their careers in the gas turbine industry. This paper presents details and lessons learned from: (i) the integration of different elements of conceptual design in an existing traditional Master of Science (MSc) course on gas turbine technology through the introduction of group design tasks and (ii) the development of an intensive course on gas turbine multidisciplinary conceptual design as a result of an international cooperation between academia and industry. Within the latter course, the students were grouped in competing teams and were asked to produce their own gas turbine conceptual design proposals within a given set of functional requirements. The main concept behind the development of the new design tasks, and the new intensive course, has been to effectively mimic the dynamics of small conceptual design teams, as often encountered in industry. The results presented are very encouraging in terms of enhancing student learning and developing engineering skills.

  • 249.
    Kyprianidis, Konstantinos
    et al.
    Cranfield University, United Kingdom.
    Grönstedt, Tomas
    Chalmers University of Technology, Sweden.
    Ogaji, S. O. T.
    Cranfield University, United Kingdom.
    Pilidis, Pericles
    Cranfield University, United Kingdom.
    Singh, Riti
    Cranfield University, United Kingdom.
    Assessment of Future Aero-engine Designs With Intercooled and Intercooled Recuperated Cores2011Ingår i: Journal of Engineering for Gas Turbines and Power, ISSN 0742-4795, Vol. 133, nr 1, artikel-id 011701Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Reduction in CO2 emissions is strongly linked with the improvement of engine specific fuel consumption, as well as the reduction in engine nacelle drag and weight. Conventional turbofan designs, however, that reduce CO2 emissions—such as increased overall pressure ratio designs—can increase the production of NOx emissions. In the present work, funded by the European Framework 6 collaborative project NEW Aero engine Core concepts (NEWAC), an aero-engine multidisciplinary design tool, Techno-economic, Environmental, and Risk Assessment for 2020 (TERA2020), has been utilized to study the potential benefits from introducing heat-exchanged cores in future turbofan engine designs. The tool comprises of various modules covering a wide range of disciplines: engine performance, engine aerodynamic and mechanical design, aircraft design and performance, emissions prediction and environmental impact, engine and airframe noise, as well as production, maintenance and direct operating costs. Fundamental performance differences between heat-exchanged cores and a conventional core are discussed and quantified. Cycle limitations imposed by mechanical considerations, operational limitations and emissions legislation are also discussed. The research work presented in this paper concludes with a full assessment at aircraft system level that reveals the significant potential performance benefits for the intercooled and intercooled recuperated cycles. An intercooled core can be designed for a significantly higher overall pressure ratio and with reduced cooling air requirements, providing a higher thermal efficiency than could otherwise be practically achieved with a conventional core. Variable geometry can be implemented to optimize the use of the intercooler for a given flight mission. An intercooled recuperated core can provide high thermal efficiency at low overall pressure ratio values and also benefit significantly from the introduction of a variable geometry low pressure turbine. The necessity of introducing novel lean-burn combustion technology to reduce NOx emissions at cruise as well as for the landing and take-off cycle, is demonstrated for both heat-exchanged cores and conventional designs. Significant benefits in terms of NOx reduction are predicted from the introduction of a variable geometry low pressure turbine in an intercooled core with lean-burn combustion technology.

  • 250.
    Kyprianidis, Konstantinos
    et al.
    Aristotle University of Thessaloniki, Thessaloniki, Greece.
    Kalfas, Anestis I.
    Aristotle University of Thessaloniki, Thessaloniki, Greece.
    Dynamic performance investigations of a turbojet engine using a cross-application visual oriented platform2008Ingår i: Aeronautical Journal, ISSN 0001-9240, Vol. 112, nr 1129, s. 161-169Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the development of visual oriented tools for the dynamic performance simulation of a turbojet engine using a cross-application approach. In particular, the study focuses on the feasibility of developing simulation models using different programming environments and linking them together using a popular spreadsheet program. As a result of this effort, a low fidelity cycle program has been created, capable of being integrated with other performance models. The amount of laboratory sessions required for student training during an educational procedure, for example for a course in gas turbine performance simulation, is greatly reduced due to the familiarity of most students with the spreadsheet software. The model results have been validated using commercially available gas turbine simulation software and experimental data from open literature. The most important finding of this study is the capability of the program to link to aircraft performance models and predict the transient working line of the engine for various initial conditions in order to dynamically simulate flight phases including take-off and landing.

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