Abstract

In this study, numerical calculations are performed to investigate steady, laminar convective heat transfer characteristics in rectangular micro channel heat sinks under constant heat fluxes. The investigations are performed at three different inlet Reynolds numbers (400,600 and 800) and constant heat fluxes (500, 1000 and 2000 kW/m2). The aspect ratios of the rectangular micro-channel are selected 1, 1.5 and 2 in the laminar flow regime, respectively. Heat transfer enhancement is the main objective of the study. Nusselt number variation and the pressure drops are found for the given parameters to find the best heat transfer enhancement. It is found that a micro-channel heat sink with square cross-sectional area can be used as an adequate configuration under laminar flow conditions.

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