Study On The Thermal System Of Parabolic Trough Solar Collectors And Its Application

Solar energy as a clean, widely-distributed resource, has become an important point for human to solve the energy crisis, and various equipments have been explored to utilize this type of energy. As one of the thermal power collectors, parabolic trough solar collector (PTSC) has been widely used and deeply studied because of its highly focused solar radiation, high-temperature steam output, and high efficiency of thermal conversion.However, due to its high construction cost, PTSC has not been popularized throughout China. Therefore, it is very urgent and important to design a new approach with high thermal efficiency and low cost.In this dissertation, theoretical research and experimental analysis of PTSC system were studied. Firstly, we discussed the structural, optical and thermal theory of the collector system, the mathematical model of the solar radiation, and the modifiication of the power conservation system. Then, a methed to calculate the surface temperature, energy efficiency, and thermal loss of PTSC system was proposed.Furthermore, the main advantages and disadvantages of the method of sun-tracking have been carefully analyzed. Then, a highly accuracy sun tracker combining computer control and sensor control were produced, and the software and hardware for the tracking system of solar energy collector were designed. Finaly, the design of single chip microprocessor control, temperature-detecting, and solar intensity detecting modules were accomplished,Additionally, the preparations and properties, the energy efficiency of the suiface coating, of thin film on the receiving tubes were investigated. Compared with other conventional energy sources, the evaluation of PTSC system have shown a low manufacturing cost while a high energy conversion efficiency.