PARAMETER OPTIMIZATION OF A MICRO HEAT SINK WITH CIRCULAR PIN-FINS

Micro heat sinks have a broad applicability in many fields such as aerospace applications, micro turbine cooling, micro reactors, electronics cooling and micro biological applications. Among different types of micro heat sinks, those with micro pin-fins are becoming popular due to their enhanced heat removal performance. However, relevant experimental data is still scarce, and few optimization studies arc present in the literature. In order to effectively optimize their performance, an extensive parametric study is necessary and should be based on a realistic model. Moreover, micro pin fin heat sinks should be optimized according to appropriate performance criteria depending on the application. The objective of this paper is to fill the research gap in micro pin fin heat sink optimization based on realistic configurations. In this paper, the parameters for micro pin optimization are the pin-fin height over diameter ratio (0.5 < H/D < 5) and the longitudinal and transverse pitch ratios (1.5 <(SL,ST)/D < 5), while Reynolds number and heat flux provided from the base of the micro heat sink are in the range of (1 < Re < 100) and (20 < q(W/cm(2))< 500), respectively. In this research, micro pin fin heat sinks are three dimensionally modeled on a one-to-one scale with the use of commercially available software COMSOL Multiphysics 3.5a. Full Navier-Stokes equations subjected to continuity and energy equations are solved for stationary conditions. To have increased computational efficiency, half of the heat sink is modeled with the use of a symmetry plane. In order to validate the use of numerical models, parametric values from previous experimental data available in the literature are exactly taken and simulated. The numerical and experimental results show a good agreement. After this validation, optimization study is performed using the three dimensional, numerical models.