Research On Convection Heat Transfer Characteristics Of Annular Microchannel Heat Sinks

Due to the continuous improvement of microelectronics technology,electronic devices with inherited circuits as the core continue to develop in the direction of miniaturization,integration and intelligence.Intelligence firmware will become the theme of future production and life.There will be effects of energy loss and increased heat flux.Electronic chips will generate a large amount of heat under long-term working conditions,which will increased heat flux.Electronic chips will increase their overall temperature to level sufficient to generate thermal strain.Therefore,temperature control of electronic chips has become a key issue in the application of electronic chips.At present,the micro-channel heat sink technology using liquid as a cooling body can effectively control the temperature of electronic equipment,but the traditional micro-channel design can no longer meet the requirements of high heat flux density and high-temperature control of electronic chips.Base on this,this paper combines the basic theories and methods of thermal design of the micro-channel of the heat sinks.A ring-shaped micro-channel heat sink model is proposed.It conducts related fluid flow and heat sink characteristics research,and the specific work is as follows:First,the numerical simulation method was used to analyze the ring-shaped micro-channel heat sinks under laminar flow(Re:576?2300).The influence of the distribution mode of inlet and outlet on the temperature uniformity was discussed separately,and compared.The results show that when the inlet and outlet are arrange crosswise,the temperature distribution is better and uniform.By comparing with the heat transfer performance of the same type of straight micro-channel heat sinks in the past,it is proved that the heat sinks performance of the new ring micro-channel is better.Secondly,a new type of ring-shaped micro-channel heat sinks is tested,and an experimental platform is independently established.The physical performance of the ring-shaped micro-channel heat sinks is verify it is heat transfer performance.The experimental data were recorded and analyzed,and then compared with the simulation results.The comparison results show that the error of the experimental and simulation results is within an acceptable range.After analyzing the uncertainty in the experiment,it can be determined that the uncertainty of the Nusselt number is 4.65%.Finally,the ring micro-channel heat sinks model is strengthened by the enhanced heat sinks theory.By adding inclined straight channels to the ring micro-channels,the secondary flow of the enhanced heat transfer model was performed numerically.By comparison with the ring-shaped micro-channel heat sinks,it was found that the maximum pressure drop of the enhanced heat transfer model was reduced by about 2.4%,and the Nussell number was increased by 21.7%.The maximum reduction in total thermal resistance is 16.4%.The influence of the structural parameters of inclined straight channels(inclination angle?and width W_th)on the heat transfer performance of the enhanced heat transfer model is discussed.When?=20°,the pressure drop ratio is small at 30°and 40°,which is a decrease of 3.9%.The average Nussell number is 8.1%higher than at 30°and 11.2%higher than at40°.The values of the width W_thare 0.72mm,1.44mm,2.16mm,and 2.88mm,respectively,and the ratio?(?=W_th/W_sc)to the width W_scof the annular micro-channel is 0.2,0.4,0.6,and 0.8,respectively.When?increases,the average Nussell number increases significantly,and when?=0.8,the average Nussell number increases by 44.1%compared to?=0.2.At the same time,the total thermal resistance showed a significant decrease.When?=0.8,the total thermal resistance decreased by 20%compared with?=0.2.