Synergistic effects of passive and active heat transfer enhancement strategies in a confined domain

With the increasing use of various cooling methods in electronics and high-temperature industrial processes, the impact of active (Piezoelectric fan – PE fan) and passive (fin) cooling methods has become of utmost importance in research. Studies coupling the usage of PE fans and fins with buoyancy-induced flows will be of great interest in several thermal equipment applications. This study utilizes numerical simulations to investigate natural convection in a cavity for three different scenarios – with fin(s), with PE fan, and with fin(s) and PE fan, concentrating on the effects of Rayleigh numbers (Ra) 10³ and 10⁵. The results show how the usage of fins, PE fan, or both together can influence the thermal transport with the variation of the Rayleigh number. It is found that the coupling effect of both methods gives the best heat transfer for any Rayleigh number among the cases considered. For Ra = 10³, three fins on the hot wall with a PE fan on the cold wall, and for Ra = 10⁵, one fin on the hot wall with a PE fan on the cold wall, transfer the heat most efficiently with an increment of 114.33 % and 18.07 % compared to a reference case of a differentially heated cavity. An increase in the number of fins acts as an impediment to the fluid flow in case of the higher Rayleigh number (10⁵), but it enhances the heat transfer rate for the lower Rayleigh number (10³).