The Analysis Of The Fluid Flow And Heat Transfer Performance In Different Structure Of The Water-cooled Heatsink

With the continuous development of modern mechanical electronic technology,various specifications of electronic equipment had been widely applied in various fields.The electronic equipment would generate heat in the normal working operation. Theheat would cause the temperature of the electronic components rise. It would causefailure or damage of electronic components if the heat had not been taken away in time.This article was based on the requirements of the rough table plane motor coil heatdissipation. The fluid flow and heat transfer performance in different structure of thewater-cooled heatsink were researched in it through the combination of theoreticalcalculation and simulation.First of all, according to the working condition of the motor coil, the articledesigned three different heatsinks. The detailed structural parameters were showed andthe characteristics of the flow channels were analyzed. The flow medium was theincompressible deionized water.Secondly, about the liquidity the article analyzed and studied the flow resistance ofthe heatsink from two aspects, straight pressure loss and local pressure loss. When thefluid flow velocity of the three heatsinks was the same, the second structure caused thebiggest pressure loss. It was bigger than the other two structure to three orders ofmagnitude. The theoretical calculation value is bigger than the simulation value due tothe actual fluid could be compressed. But the error is acceptable. The fluid flow wassteady in the straight channels, chaos in the corners and uneven in the parallel parts.Thirdly, about heat transfer the article analyzed and studied the convective heattransfer between the wall and the fluid ignoring the influence of heat conduction andthermal radiation. The heat transfer performance of the system was reflected bycalculating the local nusselt number. When the fluid flow velocity of the three heatsinkswas the same, the nusselt number of the first structure was largest, and the nusseltnumber of the second structure was smallest. But the first structure had the smallest heatdissipation area, on the contrary the third structure had the biggest one. The thirdstructure had the best cooling effect in theoretical calculation. Simulation results showed that the fluid flow should be turbulent state in order to avoid the phenomenon oftemperature gradient. The cooling effect in straight channel was poorer because of thesteady fluid flow.At last, in order to enhance the heat dissipating performance of the system, thestraight channels were improved. There were two ways, adding column structures andslotting in the bottom. Adding column structures could improve the disorder degree offluid flow, and the cooling effect was improved30%~50%. But the pressure lossincreased four times than the original structure. Slotting in the bottom could providemore heat dissipation area. When the cross-sectional area of the slots was22mm, theresults were similar to those under macro dimensions. But it belonged to the category ofthe microchannels and the macro theory was not applicable in it.