Coupling CFD and RSM to optimize the flow and heat transfer performance of a manifold microchannel heat sink

Maintaining the operating temperature within the allowable range for electronic components is crucial. This work aims to optimize the design of a heatsink manifold microchannel where the working fluid is MWCNT/water-nanofluid. The design parameters include inlet width (Linlet) , outlet width (Loutlet) , heatsink height (hf) , and MWCNT nanoparticle volume fraction in the working fluid (φ). Minimum pressure drop and minimum thermal resistance are selected as the objective functions. The finite volume method simulates the flow field and heat transfer at each design point. A regression model between the objective functions and the design variables is derived by utilizing the response surface method, and the sensitivity analysis of objective functions is performed by Pareto chart analysis. Finally, the response optimization method configures the optimal design points as Linlet, Loutlet, hf being 85, 91, 245 μm, respectively, and φ 0.016, corresponding to a pressure loss at 2677 Pa and thermal resistance at 0.8281 K/W. According to the results, the outlet width and heatsink height significantly affect the pressure drop and thermal resistance. Moreover, the physics of the flow field shows that the strength of the corner vortex and separation on the manifold can play a significant role in the thermal and hydraulic performance of the manifold microchannel heat sink. A numerical simulation has been performed to assess the regression model’s accuracy in predicting the thermal and fluid performance at the optimum point, showing a good agreement between the model prediction and the simulation results.