不同基底温度下铝基超疏水表面的抗结冰性能实验

Experimental Study on Anti-icing Performance of Aluminium-based Super-hydrophobic Surface under Different Substrate Temperatures

本文利用刻蚀方法制备了铝基超疏水表面,在环境温度20℃、相对湿度60%下进行了不同基底温度(-15℃、-20℃、-25℃、-30℃)超疏水表面的静态和动态低温液滴抗结冰性能实验研究。结果表明:超疏水表面在液滴静、动态下均表现出良好抗结冰性能;在静态液滴抗结冰实验中,随着冷表面温度的降低,超疏水表面延缓结冰的时间快速下降,当基底温度为-25℃时,其抗结冰性能发生突变,并随冷表面温度的进一步降低而表现恶化;在动态液滴抗结冰实验中,当冷表面温度为-15℃和-20℃时,低温液滴能快速从低温表面弹离,而当冷表面温度为-25℃和-30℃时,低温液滴不能从超疏水表面弹离,滞留在超疏水表面上,且快速在其上冻结,超疏水表面失去了抗结冰性能。基于相关相变成核理论,分析了其抗结冰的机理。为超疏水表面在冬季空调室外换热器上的应用提供一定参考。

The anti-icing performance of a super-hydrophobic surface, which was aluminum-based surface prepared by an etching method, at different substrate temperatures of -15, -20, -25, -30 ℃ for both static and dynamic cryogenic liquid droplets were experi- mentally investigated under an ambient temperature of 20 ℃ and relative humidity of 60%. Results showed that the super-hydrophobic surface presented good anti-icing performance under both static and dynamic conditions of liquid droplets. In static liquid droplet anti-icing experiments, the freezing time of the super-hydrophobic surface decreased rapidly as the cold surface temperature was decreased. When the substrate temperature was - 25 ℃, the anti-icing performance of the super-hydrophobie surface changed abruptly. The anti-icing per- formance of the super-hydrophobic surface worsened as the temperature of the cold surface decreased. In dynamic liquid droplet anti-icing experiments, at surface temperatures of - 15 and -20 ℃, liquid drops were able to rapidly rebound off the low-temperature surface. When the surface temperature was -25 and -30 ℃, respectively, low-temperature liquid droplets froze quickly and were incapable of rebounding off the super-hydrophobic surface, i. e. , the super-hydrophobic surface lost the ability of anti-icing. Anti-icing mechanisms were analyzed according to the phase change nucleation theory. The research results are expected to provide a reference for the application of super-hydrophobic surfaces in outside heat exchangers for winter air conditioning.