Structure Design And Analysis Of A Light-weight Thermal-electrical Conversion Device

With the development of human society,the contradiction between energy shortage and environmental pollution caused by traditional fossil fuel has become more and more intense.However,as a source of eco-energy,along with the advantage of independent power generation and flexible displacement,the dish-solar power generation system has become a potential promising form of solar energy.In this paper,in order to be compatible with a dish concentrator which is 3 meters in diameter with a flexible cable-net reflective surface,a new light-weight thermal-electric conversion device is designed to reduce weight of the whole device and increase power density.The thermal cycle of the conversion device is set as an open equivalent ideal Stirling cycle.With the pre-heat effect of the heat collector,the heat regenerator in traditional Stirling engine is replaced in order to simplify the structure of the system.Thanks to its open-form,the sealing and lubrication requirement is reduced in the engine to enhance the feasibility of the structure.Parameters of the device is set through 1^stand 2^ndorder analysis method with consideration of its structural and operating characteristics.A stable compression ratio is achieved by a scavenging valve which is connected with a rocking-block and sliding-bar mechanism.And a bugger cavity on the heat regenerator helps to make pre-heat process to be an ideal isochoric process.Comprehensive and dynamic simulation of the system is made with Simulink software after the building up of its dynamic and thermal model.The result shows that the system will eventually reach a dynamic equilibrium.And at the temperature of 800K on the heat collector,the maximum pressure of the system is 0.29 MPa,the efficiency of the thermal cycle is 28.6%,rotation speed is 3000 rpm,and the output power of the thermal engine is50W.Thus,the feasibility of the device is verified.The analysis of this paper has a certain significance for the future application of the dish-solar power generation system.