Abstract
This article presents the study on the effects of number and geometry of hollow on the heat transfer through rectangular fins attached to microchannel heat sinks. 3-dimensional models of microchannel heat sink with various hollow configurations inside the fins are developed for the analysis. The physical models are built and meshed in GAMBIT 2.3.26, and simulated by using the FVM-based CFD code, FLUENT 6.3.26. Three hollow geometries such as circular, rectangular and trapezoidal are introduced inside the rectangular fins, and simulations are performed with single hollow followed by double hollow. The results are obtained in terms of velocity profile, pressure drop, temperature distributions on the heat sink structure and base, and the total thermal resistance. It is observed that, the 'hollowed' fins could yield better hydrodynamic and thermal performances compared to the solid fins. Moreover, increase of number of hollows shows further improvement in performance, while the change in hollow geometry has negligible influence. The present model is validated with the theoretical correlations of previous workers and found in good agreement.