Optimization of a microchannel heat sink with temperature dependent fluid properties

The present study deals with the numerical optimization of microchannel heat sink with the help of surrogate analysis and evolutionary algorithm. Two design variables related to the microchannel depth, width and fin width are chosen and their ranges are decided through preliminary calculations of three-dimensional Navier-Stokes and energy equations. Objective functions related to the heat transfer and pressure drop i.e., thermal resistance and pumping power are formulated to analyze the performance of the heat sink. Water with temperature dependent thermal properties is used as coolant for steady, laminar fully developed flow in the silicon microchannels. Using the numerically evaluated objective function, polynomial response surface is constructed for each objective function. Evolutionary algorithm for multiobjective optimization is performed to obtain global Pareto optimal solutions. Trade off between objectives is found and analyzed with the design variables and flow constraints. (C) 2007 Elsevier Ltd. All rights reserved.