Numerical investigation of passive cooling of the PV module using extended fin heat sinks: A parametric analysis

One of the major issues with the Photovoltaic (PV) modules is the increase of their temperature at higher solar flux and consequently decrease of their efficiency. To stabilize the PV module efficiency at higher solar flux, effective cooling system is required. For the regions of higher solar flux (as Pakistan), this is the major concern and should be addressed properly. The current work focused on this major issue associated with the PV system and the thermal enhancement of the PV module is proposed using passive cooling system consists of extended finned based heat sink at the back of the PV module. For such kind of heat sink, the selection of appropriate number, sizing and shape of the external fins is an important issue. In this study, detailed numerical thermal analysis has been carried out considering different tube dimensions (length, diameter), number of fins and spacing between fins and the shapes of the fins. The simulations have performed using commercial code of Ansys Fluent R2 2022. The result of this study presents the optimum extended finned passive cooling structure for the PV system. The reference solar panel considered has 50 W power with length and width as 760 mm and 550 mm respectively. Due to the symmetry in geometry, a half section of the solar panel has been considered with dimensions 350 * 260 mm having symmetry boundary conditions at one end. To investigate the heat losses to the environment, sola panel section is supposed to be placed in an outer domain which act as an outer environment. This study focused on the convection heat transfer from the solar panel surface to the outer environment. The results showed that heat loss from the solar panel surface increased linearly with the increase in fin length while it sharply increased with the increase in diameter from 8 to 12 mm and then remain linear to 20 mm. The heat loss increased sharply with the increase of temperature from 333.15 K to 343.15 K and then was constant up to 353.15 K. The heat loss drastically increased with the increase in the number of the fins and consequently decrease of spacing between them. The results about the fins shaped revealed that heat loss in rectangular pin-fins was about 33.77 % higher than circular pin fins and 41.4 % higher than long rectangular fins. The results of this study will be helpful to the researchers and people working in this field.