Introduction of the rectangular hole plate in favor the performance of photovoltaic thermal solar air heaters with baffles

To further favor the performance of photovoltaic thermal solar air heaters with baffles, the simulated models of three types of photovoltaic thermal solar air heaters with baffles were established by Fluent software to analyze the effect of the arrangement of the rectangular hole plates on the flow and heat transfer characteristics of photovoltaic thermal solar air heaters with baffles. The results showed that the decrease in the intensity and the area of the separated vortex caused by the arrangement of the hole plate in photovoltaic thermal solar air heaters with baffles could decrease the pressure loss and increase the convective heat transfer coefficient between the air and the photovoltaic module surface. For the specific air volume rate ranging from 27.0 to 81.0 m(3).h(-1).m(-2), compared with Type I, the pressure losses of Type II and Type III decreased by 6.1 % similar to 17.4 % and 7.8 % similar to 20.3 %, respectively. In addition, when the specific air volume rate ranged from 13.5 to 81.0 m(3)h(-1).m(-2), compared with Type I, the power efficiency, the thermal efficiency and the exergy efficiency of Type III increased by 2.4 % similar to 4.3 %, 12.9 % similar to 20.0 % and 5.6 % similar to 8.9 %, respectively. Given the above analysis, Type III had the lowest pressure loss and the highest efficiency. Thus, Type III was the optimal structure to improve the performance of photovoltaic thermal solar air heaters with baffles.