The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Askin T. Isikveren - One of the best experts on this subject based on the ideXlab platform.
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Conceptual design of hybrid-electric Transport Aircraft
Progress in Aerospace Sciences, 2015Co-Authors: Clément Pornet, Askin T. IsikverenAbstract:The European Flightpath 2050 and corresponding Strategic Research and Innovation Agenda (SRIA) as well as the NASA Environmentally Responsible Aviation N+ series have elaborated aggressive emissions and external noise reduction targets according to chronological waypoints. In order to deliver ultra-low or even zero in-flight emissions levels, there exists an increasing amount of international research and development emphasis on electrification of the propulsion and power systems of Aircraft. Since the late 1990s, a series of experimental and a host of burgeouning commercial activities for fixed-wing aviation have focused on glider, ultra-light and light-sport airplane, and this is proving to serve as a cornerstone for more ambitious Transport Aircraft design and integration technical approaches. The introduction of hybrid-electric technology has dramatically expanded the design space and the full-potential of these technologies will be drawn through synergetic, tightly-coupled morphological and systems integration emphasizing propulsion - as exemplified by the potential afforded by distributed propulsion solutions. With the aim of expanding upon the current repository of knowledge associated with hybrid-electric propulsion systems a quad-fan arranged narrow-body Transport Aircraft equipped with two advanced Geared-Turbofans (GTF) and two Electrical Fans (EF) in an under-wing podded installation is presented in this technical article. The assessment and implications of an increasing Degree-of-Hybridization for Useful Power (HP,USE) on the overall sizing, performance as well as flight technique optimization of fuel-battery hybrid-electric Aircraft is addressed herein. The integrated performance of the concept was analyzed in terms of potential block fuel burn reduction and change in vehicular efficiency in comparison to a suitably projected conventional Aircraft employing GTF-only propulsion targeting year 2035. Results showed that by increasing HP,USE, significant fuel burn reduction can be achieved; however, this also proves to be detrimental in terms of vehicular efficiency. The potential in block fuel reduction diminishes with increasing design range - especially for low battery gravimetric specific energies. In addition, the narrow shape of the fuselage represents a volumetric constraint for the storage of the battery and typical cargo. It was concluded that the short-range/regional market segment would be the most suited for the application of such concepts. Concerning the influence of HP,USE on flight technique optimization, an increasing HP,USE was found to have a tendency of decreasing the optimum flight speed and altitude. Further investigation of more synergistic design and integration of the hybrid-electric motive power system needs to be conducted in order to explore the full benefit of such technologies.
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Integrated fuel-battery hybrid for a narrow-body sized Transport Aircraft
Aircraft Engineering and Aerospace Technology, 2014Co-Authors: Clément Pornet, Mirko Hornung, Askin T. Isikveren, S. Kaiser, Michael HornungAbstract:Purpose – The aim of this paper is to assess the potential of fuel-battery hybrid narrow-body (180PAX) Transport Aircraft according to different design ranges for an entry-into-service (EIS) of 2035. Design/methodology/approach – The philosophy used in the design of the twin-engine fuel-battery hybrid concept is to use the power of an electric motor during cruise to drive a single propulsive device, whereas the other one is powered conventionally by an advanced gas turbine. A methodology for the sizing and performance assessment of hybrid energy Aircraft was previously proposed by the authors. Based on this methodology, the overall sizing effects at Aircraft level are considered to size the hybrid Aircraft to different range applications. To evaluate the hybrid concept, performance was contrasted against a conventional Aircraft projected to EIS 2035 and sized for identical requirements. Additionally, sensitivity of the prospects against different battery technology states was analysed. Findings – The best suited Aircraft market for the application of the fuel-battery hybrid Transport Aircraft concept considered is the regional segment. Under the assumption of a battery-specific energy of 1.5 kWh/kg, block fuel reduction up to 20 per cent could be achieved concurrently with a gate-to-gate neutral energy consumption compared to an advanced gas-turbine Aircraft. However, a large increase in maximum take-off weight (MTOW) occurs resulting from battery weight, the additional electrical system weight, and the cascading sizing effects. It strongly counteracts the benefit of the hybrid-electric propulsion technology used in this concept for lower battery-specific energy and for longer design ranges. Practical implications – The findings will contribute to the evaluation of the feasibility and impact of hybrid energy Transport Aircraft as potential key enablers of the European and US aeronautical program goals towards 2035. Originality/value – The paper draws its value from the consideration of the overall sizing effects at Aircraft level and in particular the impact of the hybrid-electric propulsion system to investigate the prospects of fuel-battery hybrid narrow-body Transport Aircraft sized at different design ranges.
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a conceptual wing box weight estimation model for Transport Aircraft
Aeronautical Journal, 2013Co-Authors: R M Ajaj, M I Friswell, D D Smith, Askin T. IsikverenAbstract:This paper presents an overview of an advanced, conceptual wing-box weight estimation and sizing model for Transport Aircraft. The model is based on linear thin-walled beam theory, where the wing-box is modelled as a simple, swept tapered multi-element beam. It consists of three coupled modules, namely sizing, aeroelastic analysis, and weight prediction. The sizing module performs generic wing-box sizing using a multi-element strategy. Three design cases are considered for each wing-box element. The aeroelastic analysis module accounts for static aeroelastic requirements and estimates their impact on the wing-box sizing. The weight prediction module estimates the wing-box weight based on the sizing process, including static aeroelastic requirements. The breakdown of the models into modules increases its flexibility for future enhancements to cover complex wing geometries and advanced aerospace materials. The model has been validated using five different Transport Aircraft. It has shown to be sufficiently robust, yielding an error bandwidth of ±3%, an average error estimate of -0·2%, and a standard error estimate of 1·5%.
Dries Verstraete - One of the best experts on this subject based on the ideXlab platform.
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Long range Transport Aircraft using hydrogen fuel
International Journal of Hydrogen Energy, 2013Co-Authors: Dries VerstraeteAbstract:Abstract Hydrogen is since long seen as an outstanding candidate for an environmentally acceptable, future aviation fuel. Given that most comprehensive studies on its use in aviation were performed over two decades ago, the current article evaluates its potential as a fuel for long range Transport Aircraft at current and future technology levels. The investigations show that hydrogen has the potential to reduce the energy utilisation of long range Transport Aircraft by approximately 11%. The use of hydrogen namely allows a much smaller wing area and span since the wing size is not restricted by its fuel storage capacity. At a given price per unit energy content, the smaller wings lead to a reduction of around 30% in take-off gross weight and 3% in direct operating costs for a given fuel price per energy content. The hydrogen-fuelled Aircraft are furthermore slightly more sensitive to a possible reduction in operating empty weight in the future and 20% less sensitive to further improvements in engine thrust specific fuel consumption.
Vernon J Rossow - One of the best experts on this subject based on the ideXlab platform.
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lift generated vortex wakes of subsonic Transport Aircraft
Progress in Aerospace Sciences, 1999Co-Authors: Vernon J RossowAbstract:Abstract The flow fields of vortices, whether buoyancy-driven or lift-generated, are fascinating fluid-dynamic phenomena which often possess intense swirl velocities and complex time-dependent behavior. As part of the on-going study of vortex behavior, this paper presents a historical overview of research conducted on the structure and modification of the vortices generated by the lifting surfaces of subsonic Transport Aircraft. Although primarily presented from an experimental point of view, the derivation and use of relatively compact theoretical formulations and concepts are included. Experience with lift-generated wakes has shown that they are so complex that progress requires application of a combined theoretical and experimental research program, because either alone often leads to incorrect conclusions. The primary purpose of the research to be described is to find a way to reduce the hazard potential of lift-generated vortices shed by subsonic Transport Aircraft in the vicinity of airports during landing and takeoff operations. The information presented points out that the characteristics of lift-generated vortices are related to the aerodynamic shapes that produce them and that various arrangements of surfaces can be used to produce quite different vortex structures. It is concluded that a satisfactory aerodynamic solution to the wake-vortex problem at airports has not yet been found, but a reduction in the impact of the wake-vortex hazard on airport capacity may soon become available through wake-vortex avoidance concepts currently under study.
Salim Mkubwa Salim - One of the best experts on this subject based on the ideXlab platform.
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preliminary study of passengers body heat harvesting potential in commercial Transport Aircraft
International Journal of Engineering, 2020Co-Authors: Fairuz Izzuddin Romli, Salim Mkubwa SalimAbstract:The increasing demands for onboard electrical power of commercial Transport Aircraft have driven the search for other alternative power sources instead of relying only on the propulsion system. Along with the motivation for renewable and greener energy usage, heat energy harvesting from the passengers’ body while they are seated has been proposed to generate electrical power for the seat’s electronics. This heat energy harvesting concept uses thermoelectric devices that convert energy potential from temperature difference into electrical power based on the phenomenon known as Seebeck effects. The generated electrical power from this method heavily depends on the temperature gradient between the two sides of the thermoelectric generator. Therefore, this study has been made to demonstrate the potential of energy harvesting from the dissipated body heat of the seated Aircraft passengers. Overall, based on 20 conducted experimental cases, it has been found out that the average maximum temperature that can be possibly obtained from the passengers’ dissipated body heat is about 35.5 °C. This leads to a maximum temperature difference between the seated passengers’ body and the cabin environment of about 15.5 °C, which can be converted into about 10.23 mW of electrical power per each sensor point in the experiment using a standard thermoelectric generator.
Clément Pornet - One of the best experts on this subject based on the ideXlab platform.
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Conceptual design of hybrid-electric Transport Aircraft
Progress in Aerospace Sciences, 2015Co-Authors: Clément Pornet, Askin T. IsikverenAbstract:The European Flightpath 2050 and corresponding Strategic Research and Innovation Agenda (SRIA) as well as the NASA Environmentally Responsible Aviation N+ series have elaborated aggressive emissions and external noise reduction targets according to chronological waypoints. In order to deliver ultra-low or even zero in-flight emissions levels, there exists an increasing amount of international research and development emphasis on electrification of the propulsion and power systems of Aircraft. Since the late 1990s, a series of experimental and a host of burgeouning commercial activities for fixed-wing aviation have focused on glider, ultra-light and light-sport airplane, and this is proving to serve as a cornerstone for more ambitious Transport Aircraft design and integration technical approaches. The introduction of hybrid-electric technology has dramatically expanded the design space and the full-potential of these technologies will be drawn through synergetic, tightly-coupled morphological and systems integration emphasizing propulsion - as exemplified by the potential afforded by distributed propulsion solutions. With the aim of expanding upon the current repository of knowledge associated with hybrid-electric propulsion systems a quad-fan arranged narrow-body Transport Aircraft equipped with two advanced Geared-Turbofans (GTF) and two Electrical Fans (EF) in an under-wing podded installation is presented in this technical article. The assessment and implications of an increasing Degree-of-Hybridization for Useful Power (HP,USE) on the overall sizing, performance as well as flight technique optimization of fuel-battery hybrid-electric Aircraft is addressed herein. The integrated performance of the concept was analyzed in terms of potential block fuel burn reduction and change in vehicular efficiency in comparison to a suitably projected conventional Aircraft employing GTF-only propulsion targeting year 2035. Results showed that by increasing HP,USE, significant fuel burn reduction can be achieved; however, this also proves to be detrimental in terms of vehicular efficiency. The potential in block fuel reduction diminishes with increasing design range - especially for low battery gravimetric specific energies. In addition, the narrow shape of the fuselage represents a volumetric constraint for the storage of the battery and typical cargo. It was concluded that the short-range/regional market segment would be the most suited for the application of such concepts. Concerning the influence of HP,USE on flight technique optimization, an increasing HP,USE was found to have a tendency of decreasing the optimum flight speed and altitude. Further investigation of more synergistic design and integration of the hybrid-electric motive power system needs to be conducted in order to explore the full benefit of such technologies.
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Integrated fuel-battery hybrid for a narrow-body sized Transport Aircraft
Aircraft Engineering and Aerospace Technology, 2014Co-Authors: Clément Pornet, Mirko Hornung, Askin T. Isikveren, S. Kaiser, Michael HornungAbstract:Purpose – The aim of this paper is to assess the potential of fuel-battery hybrid narrow-body (180PAX) Transport Aircraft according to different design ranges for an entry-into-service (EIS) of 2035. Design/methodology/approach – The philosophy used in the design of the twin-engine fuel-battery hybrid concept is to use the power of an electric motor during cruise to drive a single propulsive device, whereas the other one is powered conventionally by an advanced gas turbine. A methodology for the sizing and performance assessment of hybrid energy Aircraft was previously proposed by the authors. Based on this methodology, the overall sizing effects at Aircraft level are considered to size the hybrid Aircraft to different range applications. To evaluate the hybrid concept, performance was contrasted against a conventional Aircraft projected to EIS 2035 and sized for identical requirements. Additionally, sensitivity of the prospects against different battery technology states was analysed. Findings – The best suited Aircraft market for the application of the fuel-battery hybrid Transport Aircraft concept considered is the regional segment. Under the assumption of a battery-specific energy of 1.5 kWh/kg, block fuel reduction up to 20 per cent could be achieved concurrently with a gate-to-gate neutral energy consumption compared to an advanced gas-turbine Aircraft. However, a large increase in maximum take-off weight (MTOW) occurs resulting from battery weight, the additional electrical system weight, and the cascading sizing effects. It strongly counteracts the benefit of the hybrid-electric propulsion technology used in this concept for lower battery-specific energy and for longer design ranges. Practical implications – The findings will contribute to the evaluation of the feasibility and impact of hybrid energy Transport Aircraft as potential key enablers of the European and US aeronautical program goals towards 2035. Originality/value – The paper draws its value from the consideration of the overall sizing effects at Aircraft level and in particular the impact of the hybrid-electric propulsion system to investigate the prospects of fuel-battery hybrid narrow-body Transport Aircraft sized at different design ranges.
