Modeling And Optimization Of Serpentine Channel Water-Cooling Heat Sink

With the high power density and high integration of electronic devices, their heatflux has been increasing rapidly. Therefore, an effective cooling technology is essentialfor the reliability and efficient operation of electronic devices. Traditional cooling me-thod, air cooling, is gradually insufficient for high heat flux density devices. Liquidcooling is studied increasingly widely for its higher heat transfer and higher efficiency.The geometric parameters of water-cooling heat sink have great effect on its thermalperformance. As a result, heat transfer analysis, analytical model and optimization forliquid cooling heat sink has significance for heat sink design and enhancing its thermalperformance.In this paper, a thermal resistance network model is proposed for serpentine chan-nel heat sink. The serpentine channel heat sink was separated into several units afteranalyzed its heat transfer. A thermal resistance model was built for every unit in detail,and connected these units by enthalpy thermal resistance of the liquid. This model canpredict the temperature of every node in the network, and the temperature distribution ofthe bottom surface of heat sink. At the same time, an analytical model for pressure dropof serpentine channel heat sink was also built, which can predict the total pressure dropof liquid in this serpentine channels and pressure distribution in every straight channel.In order to calculate the pressure loss caused by the bends accurate, the liquid flowat the bends was studied carefully. After a number of simulations by CFD software, weobtained the correlation for the bend loss coefficient. The correlation is valid for therange of the Reynolds number from1000to2200, and this correlation expanded therange of other parameters.And the accuracy of analytical model was verified by numerically simulations. Bycomparing the analytical model with the results of simulations for different Reynoldsnumbers and different channel parameters, the results show that they had a good agree-ment with each other. Therefore, the analytical model can be used to predict the thermalperformance and pressure drop in serpentine channel water-cooling heat sink. Finally, the parameters of serpentine channel water-cooling heat sink were opti-mized by using multi-objective genetic algorithm. The objective functions were the totalthermal resistance and total pressure drop of the heat sink. The channel width, fin width,channel height and inlet velocity are the four variables. We obtained the Pareto-optimalsolutions of optimization through calculations. After that, the sensitivities of each varia-ble to the two objective functions were also discussed.