STRUCTURAL OPTIMIZATION DESIGN AND RADIATION PERFORMANCE SIMULATION IN A DISH SOLAR COLLECTOR SYSTEM pp.279-310
Authors: (Yong Shuai, Xin-Lin Xia, He-Ping Tan, Institute of Aeronautical and Astronautical Thermophysics, School of Energy Science and Engineering, Harbin Institute of Technology, Harbin 150001, China, and others)
Abstract: Medium-high temperature application is an important topic in the solar energy field, such as solar thermal electric power systems, solar electricity generating systems, solar dynamic space power systems, etc. There is a similar process, which is the scenario of a paraboloidal dish concentrator collecting energy that is transported optically to a central cavity receiver. Solar concentrating technologies are convenient for power generation due to the high temperature achievable caused by the higher power flux. However, the factors of manufacturing or assembly errors, and nonideal sunlight with an increased angular diameter, can bring about some poor phenomena such as a bigger energy spot in the focal region, nonuniformity of heat flux distribution in the cavity receiver, or local overheating in the cavity receiver. Thermal stress concentration induced by the above-mentioned errors will further degrade the system performance. It is important to investigate the flux distribution of solar concentrating systems to optimize the system configuration. Especially in some cases, such as hydrogen production via the solar thermal gasification of biomass in supercritical condition, the flux distribution in the cavity receiver has a great effect on the efficiency of hydrogen production. The radiation flux distribution in the cavity receiver is dependent upon the directional distribution and quantity of concentrated energy. Different techniques have been developed to measure the focal flux distribution using charge coupled device (CCD) cameras . However, the development of modeling tools is still necessary to allow the detailed evaluation of the radiative heat flux distribution in the focal region of the concentrator and thus optimize the design of solar concentrator system.