基于刻蚀处理的池沸腾传热性能实验研究

Experimental study on pool boiling heat transfer performance based on etching treatment

为探究刻蚀处理铜板表面对池沸腾传热性能的改善效果,搭建了可视化实验平台,制备不同刻蚀浓度和刻蚀时间处理的表面,采用去离子水为工质,进行饱和池沸腾实验.结果表明,氨水刻蚀浓度越大,表面的换热性能越强,氨水刻蚀时间越长,表面换热性能越强.热流密度为43.2 W/cm^(2)时,0.05 mol/L氨水刻蚀4 h表面、0.05 mol/L氨水刻蚀5 h表面、0.05 mol/L氨水刻蚀8 h表面、0.03 mol/L氨水刻蚀4 h表面、0.05 mol/L氨水刻蚀4 h表面和0.10 mol/L氨水刻蚀4 h表面上的换热系数分别提高了46%、92%、105%、36%、45%、78%.此外,对其表面进行表征,结果说明了其优异的沸腾性能.刻蚀处理增强了表面粗糙度,有效面积,从而促进液体的补充,能够在较小的过热度下达到更高的临界热流密度.可视化研究结果表明,刻蚀表面具有更多的成核位点,更小的气泡离开直径和离开频率.这些结果显示出刻蚀表面强化池沸腾换热的潜力.

To investigate the improvement effect of etching-treated copper plate surface on the heat transfer performance of pool boiling,a visualization experimental platform was built to prepare surfaces treated with different etching concentrations and etching times,and saturated pool boiling experiments were conducted using deionized water as the working medium.The results showed that the greater the ammonia etching concentration,the stronger the heat transfer performance of the surface,and the longer the ammonia etching time,the stronger the heat transfer performance of the surface.The heat transfer coefficients were increased by 46%,92%,105%,36%,45%,and 78% for a heat flow density of 43.2 W/cm^(2),respectively.In addition,the surface was characterized and the results illustrated the excellent boiling performance.The etching treatment enhances the surface roughness,and effective area and thus promotes liquid replenishment,being able to achieve higher critical heat flux at smaller superheat.The visualization results show the etched surface has more nucleation sites,smaller bubble leaving diameter,and leaving frequency.These results show the potential for enhanced pool boiling heat exchange on the etched surface.