超疏水翅片表面的抑霜机理和融霜特性  

Anti-Frosting Mechanism and Frost Melting on Superhydrophobic Fin Surface

作　　者：汪峰[1] 梁彩华[1] 张小松[1] 

机构地区：[1]东南大学能源与环境学院,南京210096

出　　处：《工程热物理学报》2016年第5期1066-1070,共5页Journal of Engineering Thermophysics

基　　金：国家自然科学基金资助项目(No.51106023);"十二五"国家科技支撑计划资助项目(No.2011BAJ03B10)

摘　　要：制备了具有微纳复合结构,表面接触角和滚动角分别为159.7°和4.2°的超疏水翅片。通过可视化观测,揭示了超疏水翅片表面的抑霜机理和融霜特性,并与亲水翅片进行了对比。结霜初期,超疏水翅片表面的凝结液滴分布稀疏,呈Cassie状态;亲水翅片表面的凝结液滴分布密集,呈铺展状态,几乎覆盖整个翅片表面。超疏水翅片表面与霜层间实际接触面积小,换热热阻大,使其被霜层覆盖后仍可有效抑制霜层生长。融霜时,超疏水表面的弱黏附性导致霜层整体从翅片表面剥离和脱落,缩短了融霜时间,减少了滞留水量。A superhydrophobic fin with micro-nano structure is fabricated.Its surface contact angle and roll angle is 159.7° and 4.2° respectively.The anti-frosting mechanism and frost melting of the superhydrophobic fin are well explained.Meanwhile,comparison of frosting/defrosting characteristics is carried out with that of the hydrophilic fin,which is widely used for air source heat pumps at present.Experimental results show that the distribution of condensate droplets on the superhydrophobic fin surface is sparse,and the condensate droplets are in Cassie state,while it is serried on the hydrophilic fin surface.Condensate droplets spread on the hydrophilic fin surface,which almost cover the whole fin surface.As the contact area between the frost layer and superhydrophobic fin surface is small and the heat transfer resistance is big,the superhydrophobic surface can still restrain frost layer growth after the surface is covered by frost layer.When defrosting starts,frost layer is directly released from superhydrophobic fin surface because of the weak surface viscosity,which shortens the defrosting time and reduces the retained water mass,and saves energy consumption and improves the defrosting efficiency in turn.

关 键 词：超疏水表面 抑霜 融霜 凝结液滴 

分 类 号：TK124[动力工程及工程热物理—工程热物理]