The Experts below are selected from a list of 93 Experts worldwide ranked by ideXlab platform
Somchai Wongwises - One of the best experts on this subject based on the ideXlab platform.
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a four Power Piston low temperature differential stirling engine using simulated solar energy as a heat source
Solar Energy, 2008Co-Authors: Ancha Kongtragool, Somchai WongwisesAbstract:In this paper, the performances of a four Power-Piston, gamma-configuration, low-temperature differential Stirling engine are presented. The engine is tested with air at atmospheric pressure by using a solar simulator with four different solar intensities as a heat source. Variations in engine torque, shaft Power and brake thermal efficiency with engine speed and engine performance at various heat inputs are presented. The Beale number obtained from the testing of the engine is also investigated. The results indicate that at the maximum actual energy input of 1378 W and a heater temperature of 439 K, the engine approximately produces a maximum torque of 2.91 N m, a maximum shaft Power of 6.1 W, and a maximum brake thermal efficiency of 0.44% at 20 rpm.
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performance of a twin Power Piston low temperature differential stirling engine Powered by a solar simulator
Solar Energy, 2007Co-Authors: Bancha Kongtragool, Somchai WongwisesAbstract:Abstract This paper provides an experimental investigation on the performance of a low-temperature differential Stirling engine. In this study, a twin Power Piston, gamma-configuration, low-temperature differential Stirling engine is tested with non-pressurized air by using a solar simulator as a heat source. The engine testing is performed with four different simulated solar intensities. Variations of engine torque, shaft Power and brake thermal efficiency with engine speed and engine performance at various heat inputs are presented. The Beale number, obtained from the testing of the engine, is also investigated. The results indicate that at the maximum simulated solar intensity of 7145 W/m 2 , or heat input of 261.9 J/s, with a heater temperature of 436 K, the engine produces a maximum torque of 0.352 N m at 23.8 rpm, a maximum shaft Power of 1.69 W at 52.1 rpm, and a maximum brake thermal efficiency of 0.645% at 52.1 rpm, approximately.
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Performance of low-temperature differential Stirling engines
Renewable Energy, 2007Co-Authors: Bancha Kongtragool, Somchai WongwisesAbstract:In this paper, two single-acting, twin Power Piston and four Power Pistons, gamma-configuration, low-temperature differential Stirling engine are designed and constructed. The engine performance is tested with air at atmospheric pressure by using a gas burner as a heat source. The engine is tested with various heat inputs. Variations of engine torque, shaft Power and brake thermal efficiency at various heat inputs with engine speed and engine performance are presented. The Beale number obtained from testing of the engines is also investigated. The results indicate that, for twin Power Piston engine, at a maximum actual heat input of 2355J/s with a heater temperature of 589K, the engine produces a maximum torque of 1.222Nm at 67.7rpm, a maximum shaft Power of 11.8W at 133rpm, and a maximum brake thermal efficiency of 0.494% at 133rpm, approximately. For the four Power Pistons engine, the results indicate that at the maximum actual heat input of 4041J/s with the heater temperature of 771K, the engine produces a maximum torque of 10.55Nm at 28.5rpm, a maximum shaft Power of 32.7W at 42.1rpm, and a maximum brake thermal efficiency of 0.809% at 42.1rpm, approximately.
King Leung Wong - One of the best experts on this subject based on the ideXlab platform.
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a computational fluid dynamics study on the heat transfer characteristics of the working cycle of a low temperature differential γ type stirling engine
International Journal of Heat and Mass Transfer, 2014Co-Authors: Wen Lih Che, King Leung Wong, Yu Feng ChangAbstract:Abstract A three-dimensional compressible CFD code has been developed to study the heat transfer characteristics of a twin-Power Piston γ -type Stirling engine. The results include temperature contours, velocity vectors, and distributions of local heat flux along solid boundaries at several important time steps as well as variation of average temperatures, integrated rates of heat input, heat output, and engine Power. It is found that Impingement is the major heat transfer mechanism in the expansion and compression chambers, and the temperature distribution is highly non-uniform across the engine volume at any given moment. This study sheds light into the complex heat transfer mechanism inside the Stirling engine and is very helpful to the understanding of the fundamental process of the engine cycle.
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an experimental study on the performance of the moving regenerator for a γ type twin Power Piston stirling engine
Energy Conversion and Management, 2014Co-Authors: Wen Lih Che, King Leung Wong, Hung E CheAbstract:Abstract In this paper, a helium charge γ-type twin Power Piston Stirling engine has been studied experimentally to understand the effects of several regenerator parameters on the overall performance of the engine. The regenerator incorporated in this engine is a moving regenerator which is housed inside the displacer of the engine, and the parameters investigated include regenerator matrix material, matrices arrangement, matrix wire diameter, and fill factor. Stacked-woven metal screens have been used as regenerator matrix materials. The results include engine shaft torque, Power, and efficiency versus engine speed at several engine’s hot-end temperatures. It is found that all parameters pose significant impact on engine performance. Copper is a superior regenerator material than stainless steel for the current engine; regenerator matrix screens have to be installed in a manner that the working-gas-flow direction is normal to the surface of matrix screens; very small wire diameter results in large pressure drop and reduce regenerator effectiveness; and there exists an optimal fill factor. The study offers some important information for the design of moving regenerator in a γ-type Stirling engine.
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a numerical analysis on the performance of a pressurized twin Power Piston gamma type stirling engine
Energy Conversion and Management, 2012Co-Authors: Wen Lih Chen, King Leung WongAbstract:Abstract In this study, a prototype helium-changed twin-Power-Piston γ-type Stirling engine has been built, and some of its geometrical and operational parameters have been investigated by a numerical model. Data taken from the prototype engine have been used to correct the values of some factors in the numerical model. The results include volume and temperature variations in the expansion and compression chambers, p – v diagrams, and the effects of regeneration effectiveness, the crank radius of the Power Piston, the initial pressure of working gas, and the rotation speed on engine’s Power and efficiency. It has been found that regeneration effectiveness poses the most prominent effect on efficiency, while engine speed is most effective on the engine Power within the range of engine speed investigated in this study. This study offers invaluable guides for the design and optimization of γ-type Stirling engines with similar construction.
Bancha Kongtragool - One of the best experts on this subject based on the ideXlab platform.
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performance of a twin Power Piston low temperature differential stirling engine Powered by a solar simulator
Solar Energy, 2007Co-Authors: Bancha Kongtragool, Somchai WongwisesAbstract:Abstract This paper provides an experimental investigation on the performance of a low-temperature differential Stirling engine. In this study, a twin Power Piston, gamma-configuration, low-temperature differential Stirling engine is tested with non-pressurized air by using a solar simulator as a heat source. The engine testing is performed with four different simulated solar intensities. Variations of engine torque, shaft Power and brake thermal efficiency with engine speed and engine performance at various heat inputs are presented. The Beale number, obtained from the testing of the engine, is also investigated. The results indicate that at the maximum simulated solar intensity of 7145 W/m 2 , or heat input of 261.9 J/s, with a heater temperature of 436 K, the engine produces a maximum torque of 0.352 N m at 23.8 rpm, a maximum shaft Power of 1.69 W at 52.1 rpm, and a maximum brake thermal efficiency of 0.645% at 52.1 rpm, approximately.
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Performance of low-temperature differential Stirling engines
Renewable Energy, 2007Co-Authors: Bancha Kongtragool, Somchai WongwisesAbstract:In this paper, two single-acting, twin Power Piston and four Power Pistons, gamma-configuration, low-temperature differential Stirling engine are designed and constructed. The engine performance is tested with air at atmospheric pressure by using a gas burner as a heat source. The engine is tested with various heat inputs. Variations of engine torque, shaft Power and brake thermal efficiency at various heat inputs with engine speed and engine performance are presented. The Beale number obtained from testing of the engines is also investigated. The results indicate that, for twin Power Piston engine, at a maximum actual heat input of 2355J/s with a heater temperature of 589K, the engine produces a maximum torque of 1.222Nm at 67.7rpm, a maximum shaft Power of 11.8W at 133rpm, and a maximum brake thermal efficiency of 0.494% at 133rpm, approximately. For the four Power Pistons engine, the results indicate that at the maximum actual heat input of 4041J/s with the heater temperature of 771K, the engine produces a maximum torque of 10.55Nm at 28.5rpm, a maximum shaft Power of 32.7W at 42.1rpm, and a maximum brake thermal efficiency of 0.809% at 42.1rpm, approximately.
Valeriy Kirillov - One of the best experts on this subject based on the ideXlab platform.
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single Piston alternative to stirling engines
Applied Energy, 2012Co-Authors: Maxim Glushenkov, Martin Sprenkeler, Alexander Kronberg, Valeriy KirillovAbstract:Thermodynamic analysis of an unconventional heat engine was performed. The engine studied has a number of advantages compared to state-of-the-art Stirling engines. The main advantage of the engine proposed is its simplicity. A Power Piston is integral with a displacer and a heat regenerator. It allows solving the problem of the high-temperature sealing of the Piston and the displacer typical of all types of Stirling engines. In addition the design proposed provides ideal use of the displacer volume eliminating heat losses from outside gas circuit. Both strokes of the Piston are working ones in contrary to any other types of Piston engines. The engine can be considered as maintenance-free as it has no Piston rings or any other rubbing components requiring lubrication. The only seal is contactless and wear free. It is located in the cold part of the cylinder. As a result the leakage rate in operation can be one-two orders of magnitude as small as that in Stirling engines. Balancing of the engine is much easy compared to Stirling engines with two reciprocating masses because of the only moving part inside the engine cylinder. The engine suits ideally to be fuelled with “difficult” fuels such as bio oil and can be used as a prime mover for micro-CHP systems.
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single Piston alternative to stirling engines
Applied Energy, 2012Co-Authors: Maxim Glushenkov, Martin Sprenkeler, Alexander Kronberg, Valeriy KirillovAbstract:Abstract Thermodynamic analysis of an unconventional heat engine was performed. The engine studied has a number of advantages compared to state-of-the-art Stirling engines. The main advantage of the engine proposed is its simplicity. A Power Piston is integral with a displacer and a heat regenerator. It allows solving the problem of the high-temperature sealing of the Piston and the displacer typical of all types of Stirling engines. In addition the design proposed provides ideal use of the displacer volume eliminating heat losses from outside gas circuit. Both strokes of the Piston are working ones in contrary to any other types of Piston engines. The engine can be considered as maintenance-free as it has no Piston rings or any other rubbing components requiring lubrication. The only seal is contactless and wear free. It is located in the cold part of the cylinder. As a result the leakage rate in operation can be one-two orders of magnitude as small as that in Stirling engines. Balancing of the engine is much easy compared to Stirling engines with two reciprocating masses because of the only moving part inside the engine cylinder. The engine suits ideally to be fuelled with “difficult” fuels such as bio oil and can be used as a prime mover for micro-CHP systems. The thermodynamic model developed incorporates non-ideal features of the cycle, such as specific regenerator efficiency, dead volumes and other geometrical parameters of the engine. The model shows that the energy efficiency is highly sensitive to regenerator performance. For realistic geometric and operating parameters and the regenerator efficiency of about 95% the ultimate energy conversion efficiency of the engine proposed can be as high as 40–50%. A prototype of the engine was built and the feasibility of the engine concept was demonstrated.
Wen Lih Che - One of the best experts on this subject based on the ideXlab platform.
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a computational fluid dynamics study on the heat transfer characteristics of the working cycle of a low temperature differential γ type stirling engine
International Journal of Heat and Mass Transfer, 2014Co-Authors: Wen Lih Che, King Leung Wong, Yu Feng ChangAbstract:Abstract A three-dimensional compressible CFD code has been developed to study the heat transfer characteristics of a twin-Power Piston γ -type Stirling engine. The results include temperature contours, velocity vectors, and distributions of local heat flux along solid boundaries at several important time steps as well as variation of average temperatures, integrated rates of heat input, heat output, and engine Power. It is found that Impingement is the major heat transfer mechanism in the expansion and compression chambers, and the temperature distribution is highly non-uniform across the engine volume at any given moment. This study sheds light into the complex heat transfer mechanism inside the Stirling engine and is very helpful to the understanding of the fundamental process of the engine cycle.
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an experimental study on the performance of the moving regenerator for a γ type twin Power Piston stirling engine
Energy Conversion and Management, 2014Co-Authors: Wen Lih Che, King Leung Wong, Hung E CheAbstract:Abstract In this paper, a helium charge γ-type twin Power Piston Stirling engine has been studied experimentally to understand the effects of several regenerator parameters on the overall performance of the engine. The regenerator incorporated in this engine is a moving regenerator which is housed inside the displacer of the engine, and the parameters investigated include regenerator matrix material, matrices arrangement, matrix wire diameter, and fill factor. Stacked-woven metal screens have been used as regenerator matrix materials. The results include engine shaft torque, Power, and efficiency versus engine speed at several engine’s hot-end temperatures. It is found that all parameters pose significant impact on engine performance. Copper is a superior regenerator material than stainless steel for the current engine; regenerator matrix screens have to be installed in a manner that the working-gas-flow direction is normal to the surface of matrix screens; very small wire diameter results in large pressure drop and reduce regenerator effectiveness; and there exists an optimal fill factor. The study offers some important information for the design of moving regenerator in a γ-type Stirling engine.
