The Experts below are selected from a list of 321 Experts worldwide ranked by ideXlab platform
F Martins - One of the best experts on this subject based on the ideXlab platform.
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Life Cycle Analysis of biodiesel production
Fuel Processing Technology, 2011Co-Authors: Marta G. Varanda, G Pinto, F MartinsAbstract:Abstract Biodiesel has attracted considerable attention as a renewable, biodegradable, and nontoxic fuel and can contribute to solving the energy problems, significantly reducing the emission of gases which cause global warming. The first stage of this work was to simulate different alternative processes for producing biodiesel. The method used for the production of biodiesel is the transesterification of vegetable oils with an alcohol in the presence of a catalyst. The raw materials used were palm oils and waste cooking oil. The second stage was a life Cycle Analysis for all alternatives under study, followed by an economic Analysis for the alternatives that present minor impacts and which are more promising from an economic point of view. Finally, we proceeded to compare the different alternatives from both the point of view of life Cycle and economic Analysis. The feasibility of all processes was proven and the biodiesel obtained had good specifications. From the standpoint of life Cycle Analysis, the best alternative was the process of alkaline catalysis with acid pre-treatment for waste cooking oil. The economic Analysis was done to the previous mentioned process and to the process that uses raw virgin oils, methanol, and sodium hydroxide. This process has lower investment costs but the process of alkaline catalysis with acid pre-treatment, whose main raw material is waste oil, is much more profitable and has less environmental impacts.
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Life Cycle Analysis of biodiesel production
Fuel Processing Technology, 2011Co-Authors: Marta G. Varanda, G Pinto, F MartinsAbstract:Biodiesel has attracted considerable attention as a renewable, biodegradable, and nontoxic fuel and can contribute to solving the energy problems, significantly reducing the emission of gases which cause global warming. The first stage of this work was to simulate different alternative processes for producing biodiesel. The method used for the production of biodiesel is the transesterification of vegetable oils with an alcohol in the presence of a catalyst. The raw materials used were palm oils and waste cooking oil. The second stage was a life Cycle Analysis for all alternatives under study, followed by an economic Analysis for the alternatives that present minor impacts and which are more promising from an economic point of view. Finally, we proceeded to compare the different alternatives from both the point of view of life Cycle and economic Analysis. The feasibility of all processes was proven and the biodiesel obtained had good specifications. From the standpoint of life Cycle Analysis, the best alternative was the process of alkaline catalysis with acid pre-treatment for waste cooking oil. The economic Analysis was done to the previous mentioned process and to the process that uses raw virgin oils, methanol, and sodium hydroxide. This process has lower investment costs but the process of alkaline catalysis with acid pre-treatment, whose main raw material is waste oil, is much more profitable and has less environmental impacts. © 2011 Elsevier B.V.
Jeffrey A. Roux - One of the best experts on this subject based on the ideXlab platform.
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Parametric Cycle Analysis of an ideal pulse detonation engine – Supersonic branch
Thermal science and engineering, 2018Co-Authors: Jeffrey A. RouxAbstract:Abstract The purpose of this note is to present a mathematical description of an ideal pulse detonation engine (PDE) based on parametric Cycle Analysis for supersonic heat addition. The parametric Cycle Analysis is presented in terms of parameters similar to those for the well-known parametric Cycle analyses for the ideal ramjet engine. The performance characteristics of specific thrust, thrust-specific fuel consumption, fuel-to-air ratio, thermal efficiency, propulsive efficiency, overall efficiency, and thrust flux are illustrated as functions of the two parameters: inlet/diffuser exit Mach number, M2 > 1, and freestream Mach number, Mo. This work provides algebraic equations which can be used quickly to investigate the ideal supersonic combustion PDE performance as a function of a variety of input parameters. It is hoped that this work will aid in exploring the performance of the ideal supersonic combustion PDE from a big picture perspective.
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Parametric Cycle Analysis of an Ideal Pulse Detonation Engine
Journal of Thermophysics and Heat Transfer, 2015Co-Authors: Jeffrey A. RouxAbstract:The purpose of this work is to present a mathematical description of an ideal pulse-detonation-engine-based on parametric Cycle Analysis. The parametric Cycle Analysis is presented in terms of parameters similar to those for the well-known parametric Cycle analyses for the ideal turbojet engine and the ideal ramjet engine. The performance characteristics of specific thrust, thrust-specific fuel consumption, fuel-to-air ratio, thermal efficiency, propulsive efficiency, and overall efficiency are presented as functions of the two variables: compressor total pressure ratio πc and freestream flight Mach number Mo. This work provides algebraic equations that can be used conveniently to investigate the ideal pulse detonation engine performance as a function of a variety of input parameters. It is hoped that this work will aid in exploring the performance of the ideal pulse detonation engine from a big-picture perspective.
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Parametric Ideal Scramjet Cycle Analysis
Journal of Thermophysics and Heat Transfer, 2011Co-Authors: Jeffrey A. RouxAbstract:Parametric Cycle analyses for the ideal ramjet, ideal turbojet, and ideal turbofan engines are well known and documented. The parametric mathematical descriptions of these ideal propulsion systems are useful for understanding the advantages and useful operation conditions when comparing these engines with one another and with mission requirements. It is also known that the scramjet engine is superior in producing specific thrust over these other engineswhen operating at hypersonicMachnumbers. The purpose of this work is to present a parametric Cycle Analysis for the ideal scramjet. This permits the description of the ideal scramjet via simple algebraic equations similar to that for the ideal ramjet, ideal turbojet, and ideal turbofan engines.
Marta G. Varanda - One of the best experts on this subject based on the ideXlab platform.
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Life Cycle Analysis of biodiesel production
Fuel Processing Technology, 2011Co-Authors: Marta G. Varanda, G Pinto, F MartinsAbstract:Abstract Biodiesel has attracted considerable attention as a renewable, biodegradable, and nontoxic fuel and can contribute to solving the energy problems, significantly reducing the emission of gases which cause global warming. The first stage of this work was to simulate different alternative processes for producing biodiesel. The method used for the production of biodiesel is the transesterification of vegetable oils with an alcohol in the presence of a catalyst. The raw materials used were palm oils and waste cooking oil. The second stage was a life Cycle Analysis for all alternatives under study, followed by an economic Analysis for the alternatives that present minor impacts and which are more promising from an economic point of view. Finally, we proceeded to compare the different alternatives from both the point of view of life Cycle and economic Analysis. The feasibility of all processes was proven and the biodiesel obtained had good specifications. From the standpoint of life Cycle Analysis, the best alternative was the process of alkaline catalysis with acid pre-treatment for waste cooking oil. The economic Analysis was done to the previous mentioned process and to the process that uses raw virgin oils, methanol, and sodium hydroxide. This process has lower investment costs but the process of alkaline catalysis with acid pre-treatment, whose main raw material is waste oil, is much more profitable and has less environmental impacts.
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Life Cycle Analysis of biodiesel production
Fuel Processing Technology, 2011Co-Authors: Marta G. Varanda, G Pinto, F MartinsAbstract:Biodiesel has attracted considerable attention as a renewable, biodegradable, and nontoxic fuel and can contribute to solving the energy problems, significantly reducing the emission of gases which cause global warming. The first stage of this work was to simulate different alternative processes for producing biodiesel. The method used for the production of biodiesel is the transesterification of vegetable oils with an alcohol in the presence of a catalyst. The raw materials used were palm oils and waste cooking oil. The second stage was a life Cycle Analysis for all alternatives under study, followed by an economic Analysis for the alternatives that present minor impacts and which are more promising from an economic point of view. Finally, we proceeded to compare the different alternatives from both the point of view of life Cycle and economic Analysis. The feasibility of all processes was proven and the biodiesel obtained had good specifications. From the standpoint of life Cycle Analysis, the best alternative was the process of alkaline catalysis with acid pre-treatment for waste cooking oil. The economic Analysis was done to the previous mentioned process and to the process that uses raw virgin oils, methanol, and sodium hydroxide. This process has lower investment costs but the process of alkaline catalysis with acid pre-treatment, whose main raw material is waste oil, is much more profitable and has less environmental impacts. © 2011 Elsevier B.V.
B. Sørensen - One of the best experts on this subject based on the ideXlab platform.
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Life-Cycle Analysis of renewable energy systems
Renewable Energy, 1994Co-Authors: B. SørensenAbstract:An imlementation of life-Cycle Analysis (LCA) for energy systems is presented and applied to two renewable energy systems (wind turbines and building-integrated photovoltaic modules) and compared with coal plants. © 1994.
Ashley Kells - One of the best experts on this subject based on the ideXlab platform.
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Fuel cell hybrid taxi life Cycle Analysis
Energy Policy, 2011Co-Authors: Patrícia Baptista, João Bravo, Paul Adcock, Carla Silva, João Ribau, Ashley KellsAbstract:A small fleet of classic London Taxis (Black cabs) equipped with hydrogen fuel cell power systems is being prepared for demonstration during the 2012 London Olympics. This paper presents a Life Cycle Analysis for these vehicles in terms of energy consumption and CO2 emissions, focusing on the impacts of alternative vehicle technologies for the Taxi, combining the fuel life Cycle (Tank-to-Wheel and Well-to-Tank) and vehicle materials Cradle-to-Grave. An internal combustion engine diesel taxi was used as the reference vehicle for the currently available technology. This is compared to battery and fuel cell vehicle configurations. Accordingly, the following energy pathways are compared: diesel, electricity and hydrogen (derived from natural gas steam reforming). Full Life Cycle Analysis, using the PCO-CENEX drive Cycle, (derived from actual London Taxi drive Cycles) shows that the fuel cell powered vehicle configurations have lower energy consumption (4.34Â MJ/km) and CO2 emissions (235Â g/km) than both the ICE Diesel (9.54Â MJ/km and 738Â g/km) and the battery electric vehicle (5.81Â MJ/km and 269Â g/km).
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Fuel cell hybrid taxi well-to-wheel life-Cycle Analysis
World Electric Vehicle Journal, 2011Co-Authors: Patrícia Baptista, João Bravo, Paul Adcock, Carla Silva, João Ribau, Ashley KellsAbstract:A small fleet of classic London Taxis (Black cabs) equipped with hydrogen fuel cell power systems is being prepared for demonstration during the 2012 London Olympics. This paper presents a Life Cycle Analysis for these vehicles in terms of energy consumption and CO2emissions, focusing on the impacts of alternative vehicle technologies for the Taxi, combining the fuel life Cycle (Tank-to-Wheel and Well-to-Tank) and vehicle materials Cradle-to-Grave. An internal combustion engine diesel taxi was used as the reference vehicle for the currently available technology. This is compared to battery and fuel cell vehicle configurations. Accordingly, the following energy pathways are compared: diesel, electricity and hydrogen (derived from natural gas steam reforming).Full Life Cycle Analysis, using the PCO-CENEX drive Cycle, (derived from actual London Taxi drive Cycles) shows that the fuel cell powered vehicle configurations have lower energy consumption (4.34MJ/km) and CO2emissions (235g/km) than both the ICE Diesel (9.54MJ/km and 738g/km) and the battery electric vehicle (5.81MJ/km and 269g/km). © 2011 Elsevier Ltd.
