| In recent years,with the trend toward high performance and miniaturization of many electronic components.The heat power per unit area of high-performance electronic components has dramatically increased,which will inevitably result in an increase in thermal stress and an increase in surface temperature[1],which greatly reduces its performance.This article mainly uses the experimental method to study the sintering copper powder wick core parameters of the temperature plate suction core made of copper particles with different particle sizes.The copper powder pillars are evenly distributed inside the vapor chamber.Such a kind of the structural design not only solves the deformation problem,but also reduces the liquid return path and improves the heat transfer performance of the vapor chamber greatly.First,four kinds of capillary wicks were selected in the experiment,with the particle size of 30?m,50?m,90?m and mixed particle size?30?m&90?m?.By comparative experiments,the effects of particle size on the performance of the vapor chambers were investigated.At the same heating power and filling ratio,the thermal resistance of the vapor chamber with the particle size of 90?m reaches the minimum value?0.09°C/W?.This shows that a capillary wick with a larger particle size is beneficial to improving the performance of the vapor chamber.Compared with the pure copper plate,the average temperature of the temperature plate is better.Secondly,the effect of filling ratio on the heat transfer performance was also studied,which is 70%,90%,120%and 160%.Experiments show that,for a vapor chamber with a particle size of 90?m,the best charge ratio is about 90%,and the thermal resistance of the temperature plate is 0.14°C/W.Larger or smaller filling rates may increase the thermal resistance of the vapor chamber.For the two heating area heat sources?15mm·15mm and 30mm·30mm?,experimental tests have found that the heating area has a great influence on the thermal resistance of the isothermal plate.Under the same charging rate,the thermal resistance corresponding to a small area heat source is much higher than the corresponding thermal resistance value of a large area heat source.For a small area heat source,the advantages of the heat exchange performance of the isothermal plate can be highlighted,and it is better than the pure copper plate.The start-up performances of the heat exchange plates with different heat sources were studied.The experiments show that the start-up time of the temperature equalization plate is more rapid,reaching a stable value after about 200s,and the start-up time of the pure copper plate is 600s.The temperature uniformity plate with smaller particle size has better starting performance.Finally,the temperature of the plate was studied visually.The research shows that the filling rate has a great influence on the boiling mode of the soaking plate.In the case where the charge rate is less than 100%,the boiling mode of the sintered copper powder type evaporation plate occurs at the evaporation mode of the thin liquid film rather than the pool boiling phenomenon usually considered.Through the study of this paper,it is found that the use of a porous column support structure can effectively shorten the liquid return path,and the performance of the temperature equalization plate can be greatly improved.The overall performance of the temperature equalization plate with a larger particle size is better. |
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