Experimental investigation on thermal management of a photovoltaic module using water-jet impingement cooling

摘要

Cooling of photovoltaic (PV) modules is investigated indoors using a multi-nozzle jet impingement cooling (JIC) system with water as the coolant. The focus is to develop extensive study on the effects of the number of nozzles, their sizes (diameter), and the dimensionless nozzle-to-PV spacing on the overall performance of the JIC system. Temperature uniformity index, a distinctive key parameter, is introduced to assess the effectiveness and desirability of the JIC system from the thermal point of view. Response Surface Methodology (RSM) is developed to determine the optimal operating conditions of the JIC system. The results reveal that the electrical efficiency of the PV module is improved by an increase in the liquid mass flow rate. The output power of the PV module is also enhanced with the number of nozzles; the reverse is true for the diameter of nozzle and the nozzle-to-PV spacing. Appropriate temperature uniformity can be achieved by an optimum design of the JIC system. The results of RSM demonstrate that the JIC system with optimum parameters not only enhances considerably the output electrical power, but also reduces the operating temperature of the PV module while keeps it uniform for each individual cell. Average surface temperature of the PV module decreases from 63.95 degrees C to 33.68 C by using a set of optimal parameters. Maximum enhancement in the output power of the PV/JIC system is 47.67% in the optimum conditions. The best temperature uniformity is attained for the minimum nozzle-to-PV spacing (5mm), the minimum nozzle diameter (1mm) and the maximum number of nozzles (24).