Optimizing Minichannel Heat Sink Design: A Combined Numerical and Experimental Analysis of Inlet/Outlet Configurations and Pin Fin Enhancements

Abstract

The present study investigated the effect of inlet location, counterflow and parallel flow configurations, and rib addition (pin fins) on the performance factor of minichannel heat sinks. Different rib spacings were investigated in Models D, E, and F, which are 5, 7, and 9 mm, respectively, all using counterflow. These models used ribs with a diameter of 1 mm. In addition, Models G and H were presented to explore different rib sizes (1.5 and 2 mm) while maintaining a rib spacing of 5 mm under counterflow conditions. All effects were studied numerically using ANSYS Fluent 19R3 under laminar coolant flow, with Reynolds numbers ranging from 1190 to 1900. The study also included fabricating two models: the conventional model and the optimized model, and comparing their results with the numerical results. The comparison indicated a satisfactory convergence between the experimental and numerical results. The results revealed that all modifications significantly improved the temperature distribution and overall performance factor (OPF). Model B outperformed the conventional model in terms of pressure drop and heat resistance, achieving improvements of 46% and 40%, respectively. Furthermore, Model D outperformed Model B in Nusselt number by 31.375%. Notably, Model D showed the highest OPF and most consistent core temperature among the models, confirming its status as the ideal design, with an OPF of 2 compared with the conventional model.