颗粒烧结多孔芯蒸发/沸腾换热的实验研究

An Experimental study on Evaporation/Boiling Heat Transfer in Sintered Porous Wick

以水为工质,在热管工况(真空减压条件)下对具有不同颗粒种类(电解粉和水雾粉)、颗粒直径和多孔芯厚度的铜粉颗粒烧结多孔芯进行了蒸发/沸腾换热实验研究。结果表明:随着热流密度的上升,换热系数先上升后下降;在孔隙率一定的情况下,存在最优多孔芯厚度使得蒸发/沸腾换热性能最佳;当多孔芯厚度一定时,在热流密度不是很大时存在着最优孔隙率,但是当热流密度较大时,孔隙率越小的多孔芯的换热性能越好。本文还总结了蒸发/沸腾换热模型,对实验数据进行了合理解释。

An experimental setup was designed and established to study the evaporation/boiling heat transfer in particle sintered porous wick under the working condition of heat pipe.The effects of particle size as well as the thickness and volumetric porosity of porous wick on evaporation/boiling heat transfer were investigated using distilled water as working media.It was found that for the fixed particle size and porosity,there exists an optimal wick thickness to achieve the maximum heat transfer coefficient.For the fixed thickness of porous wick,there is an optimal porosity when the heat flux is relatively low,however,the smaller the porosity is,and the higher the heat transfer coefficient is when heat flux is relatively high.An evaporation/boiling heat transfer model was also summarized to give plausible explanations of experimental results.