Solar Thermal Conversion Mechanism Research And Experimental System Project Design Of STP

Solar Thermal Propulsion (STP) is a new kind of concept and technology. It is mainly composed of solar concentrator, absorber/thruster and propellant supply system. It uses focused sunlight to heat a lightweight propellant, such as hydrogen, which is then expanded out a nozzle for thrust. As we all know, solar radiation energy can get anywhere in space and has no contamination. Therefore STP will reduce space pollution greatly. STP doesn't require electric power conversion and energy management system, so its structure is relatively simple and it has a high solar energy utilizing efficiency. It has performance advantages of high specific impulse and moderate thrust levels. As a repeated using space propulsion, STP is enormously potential for development. This paper aimed to research the conversion mechanism between sunlight and heat in STP, to compare and analyze different propulsion projects, materials and energy transition styles, to design pivotal components, such as primary solar concentrator, refractive secondary concentrator and absorber/thruster, and to compute the performance of STP. The contents and values of this paper include:1. Summarizing the research actuality, application and development of STP, and pointing out the developing necessity and imminence in China.2. Analyzing the working principles, structures and characteristics of different STP projects, and especially researching the basic theory of heating propellant which took advantage of the collected solar radiant energy. This can be employed as important guidance for designing.3. Analyzing the style selections, design fundamentals and machining techniques of the pivotal components, and demonstrating the correlation formula and the structure dimensions.4. Presenting the performance evaluation methods of STP according to the law of energy conservation, radiation heat transfer principle and heat transfer theory, showing the result that STP has advantages of high specific impulse (5000-9000 m/s), wide thrust level (0.6-60 N) using hydrogen as the propellant, and drawing the change relations of performance parameters among concentration ratio, solar radiation flux density and mass flow rate. This provides some significant theoretical references for selecting design parameters and further research.