Entropy analysis and parametric optimization on the Nano fluid flow and heat transfer of a pin-fin heatsink with the splitter using the two-phase mixture model

The nanofluid (NF) flow rate and concentration (φ) in a pin-fin heat sink with the splitter (WS) were numerically investigated and the optimum Re and φ values were determined by applying a parametric optimization analysis on the thermal and frictional entropy generation rates (S˙_th and S˙_fr). To this end, the discretization of the governing equation was done by the second-order upwind scheme, the finite volume method. The results were compared with those obtained for the pin-fin heatsink without the splitter (WOS). Based on the findings, the intensification of Re and φ reduces S˙_th by almost 43-45% and 10-13%, respectively, for both WS and WOS heatsinks. An insignificant difference between S˙_th of two configurations was obtained (0.37-2.93%). Although S˙_fr diminishes by 12% as φ intensifies from 0 to 1%, the escalation of Re from 500 to 2000 intensifies S˙_fr by 2312% and 4618% in WS and WOS heatsinks, respectively. In addition, S˙_fr of WS heatsink is nearly 43-48% lower than that WOS heatsink due to using splitters. The absence of the splitter in the WOS heatsink leads to a delay in flow separation from the pin-fin bodies and deteriorates the heat dissipation, thereby increasing the CPU temperature and S˙_fr intensification.