Model construction and photothermal conversion performance of a miniature non-imaging concentrator for capturing solar radiation in full sunlight

Non-imaging concentrators have been widely applied in the field of solar concentration. However, there are also unfavorable factors such as short effective working time, high production cost of curved reflector, which restrict its wider application in industry and agriculture. Therefore, this paper proposes a miniature non-imaging concentrator (FC-CPC) that can capture solar radiation in full sunlight based on the principle of edge ray. The geometric structure of the FC-CPC was optimized using the VC++ program, resulting in the development of an all-equal multi-section non-imaging concentrator (FM-CPC). On this basis, the optical performance and photothermal conversion performance of FM -CPC during operation were investigated. The results indicate that the average optical efficiency of FM-CPC direct radiation is 50.9 %, and the energy density distribution on the absorber surface is relatively uniform with a low energy density peak. The photothermal conversion system integrated with the FM-CPC shows an increase in collection efficiency as air flow rate increases, reaching a highest average efficiency of 54.1 %.