铜粉粒径对烧结式微热管传热性能的影响

摘　要：通过实验，探讨了水雾化铜粉（water atomization, wa）的粒径对吸液芯孔隙率及烧结式微热管传热性能的影响。揭示了外径为5mm、6mm及8mm，吸液芯厚度为0.5mm-0.6mm的热管在不同铜粉粒径大小及配比的情况下的传热特性。结果发现，铜粉粒径分布比较集中时，增大铜粉平均粒径，吸液芯的孔隙率和热管的极限传输功率q max都会增大，热管的冷凝端温差及总热阻会略微减小。将不同粒径范围的铜粉进行混合时，热管的冷凝端温差及总热阻在不同外径的热管内规律不同；小粒径铜粉比例为70%时热管q max小；将其粒径减小，q max会降低；大粒径铜粉比例为70%时，热管q max仅次于大粒径铜粉比例为的。研究结果表明，铜粉粒径的范围越接近于一个值，热管的性能越优，平均粒径大小为165±15um的铜粉适合于制作薄壁烧结式微热管。

 

abstract: an experiment on how particle size of water atomized copper powder(water atomization, wa) effects porosity of wicks and heat transfer performance of heat pipes ispresented in this study. micro sintered heat pipes with outer diameters of 5 mm、6mm and 8mmand thickness ranging from 0.5 to 0.6 mm of wicks sintered in different-sized particles are discussed. the result shows that, when the copper particle size distribution is concentrated, increasing the average particle size of copper powder will make the porosity of wick in heat pipes as well as the maximum heat transfer power（q max） increase, while the temperature difference on condensation and total thermal resistance reduce slightly. when particles in different range of sizes are mixed, temperature difference on condensation and total thermal resistance of heat pipes with different outer diameters are different. heat pipes sintered with 70% small-sized particles have the lowest q max. and the small-sized particles reducing in size can result in the q maxdecreasing. q max of heat pipes sintered with 70% large-sized particles is only second to that sintered with large-sized particles. it is also found that the more concentrated in a value the range of particle sizes is, the more excellent the performance of heat pipe will be. the powder in the average particle size ranging from 150 to 180um is proved to be appropriate for manufacture of heat pipes.