Numerical Simulation And Optimization Design Of Cooling Plate In Indirect Liquid Cooling System

With the continuous progress of integration and packaging technology,the performance of chips is constantly improved,but the thermal management problem is becoming more and more serious.For high thermal design power consumption,especially for components with high heat flux,the traditional air-cooling cooling technology has shown obvious shortcoming:not only can not effectively control the maximum temperature,but also has a disadvantage in the control of the surface temperature uniformity of power components.Indirect liquid cooling system uses water cooling plate to isolate electronic equipment from coolant,and fits the water cooling plate to the power component package structure.The circulating flow of coolant in the pipeline is realized through pump,thus the targeted heat dissipation of power components is completed.The whole system is compact in structure,with large thermal load capacity,and is much simpler to maintain than direct liquid cooling system.In this paper,the flow and heat transfer characteristics of pin fin array cold plate are analyzed by numerical simulation,and the optimization design and analysis of cylindrical pin fin array cold plate are carried out.The main research work and achievements are as follows:Firstly,by comparing the simulation results with the experimental results,the simulation method is modified;the geometric model and numerical simulation parameters are verified;and the validity of the Standard k-ε model and Scalable Wall Function in solving the subject of the flow heat transfer performance of water-cooled plates is determined.Then,the differences of flow and heat transfer performance caused by different pin fin types were analyzed.Combined with the physical field distribution nephogram,the flow distribution and heat dissipation results of the working medium in the cold plate were characterized.It was found that the maximum temperature of each cold plate is controlled within 42℃.And the cylindrical pin fin array cold plate had the best heat dissipation performance,lower thermal resistance,more uniform temperature distribution of the power module;At the same time,the cold plate with triangular prism and pentagonal prism has better flow characteristics,better flow uniformity and smaller pressure drop.Finally,by arranging baffles in the cylindrical pin fin array cold plate,the flow and heat transfer performance of the cold plate is analyzed.It is found that the arrangement of baffle reduces the number of pin fins,which has a negative impact on the heat dissipation performance of the cold plate;And the effect of baffles on the flow and heat transfer of cold plate is affected by the shape of baffles and the number of layers.The arrangement of long straight baffles is beneficial to improve the flow characteristics of cooling fluid,especially in the high Reynolds number and high pump power conditions,which can significantly improve the flow uniformity,and it can reduce the pressure drop by about 13%;The results show that the cooling plate with three layers of long straight baffles has the best flow uniformity.The results show that the addition of circular baffle can only optimize the flow resistance characteristics of the cold plate in a small extent in the case of high Reynolds number and only one baffle layer,and the other cases do not show the optimization effect,even the pressure drop of the cold plate increases greatly because of the addition of the baffle;In addition,the addition of arc baffle has a very negative impact on the heat dissipation performance of the cold plate.The heat dissipation capacity,thermal resistance,temperature uniformity and maximum temperature of the cold plate are obviously worse than those of the cylindrical pin fin array cold plate.However,it is worth mentioned that the flow uniformity of the pin fin array cold plate with one or two circular baffles under high Reynolds number and high pump power conditions reflects certain advantages.