Heat exchanger capable of automatically defrosting or deicing

Abstract

A heat exchanger capable of automatically defrosting or deicing includes row tubes and fins. A refrigerating medium can be led into the row tubes. The fins are arranged on an outer wall of the row tube. And heights of the fins extend in a radial direction of the row tube. Each of the fins include a first heat conducting part and a second heat conducting part that are connected with the row tube in sequence. A thermal conductivity of the second heat conducting part is smaller than a thermal conductivity of the first heat conducting part and a thermal conductivity of the row tube. An outer surface of the first heat conducting part and an outer surface of the row tube are both coated with a micron or nanometer hydrophobic layer, which is a hydrophobic coating or a hydrophobic oil film.

What is claimed is: 
     
         1 . A heat exchanger capable of automatically defrosting or deicing, comprising heat exchange assemblies,
 wherein each of the heat exchange assemblies comprises a row tube configured to fill with refrigerating medium and fins arranged on an outer wall of the row tube, and heights of the fin extend in a radial direction of the row tube;   each of the fins comprises a first heat conducting part and a second heat conducting part that are connected with the row tube in sequence, and a thermal conductivity of the second heat conducting part is smaller than a thermal conductivity of the first heat conducting part and a thermal conductivity of the row tube; and   an outer surface of the first heat conducting part and an outer surface of the row tube are both coated with a micron or nanometer hydrophobic layer, which is a hydrophobic coating or a hydrophobic oil film.   
     
     
         2 . The heat exchanger capable of automatically defrosting or deicing according to  claim 1 , wherein the hydrophobic coating is a fluorocarbon coating, a polytetrafluoroethylene coating or a silicone hydrophobic coating. 
     
     
         3 . The heat exchanger capable of automatically defrosting or deicing according to  claim 1 , wherein the hydrophobic oil film is a vaseline oil film, an animal oil film, a vegetable oil film or a mineral oil film. 
     
     
         4 . The heat exchanger capable of automatically defrosting or deicing according to  claim 1 , wherein at least two heat exchange assemblies are arranged at intervals, the heat exchanger further comprises a connecting tube and a thermal insulation layer, first ends of two adjacent rows tubes are communicated with each other by the connecting tube, the thermal insulation layer wraps the connecting tube, and a thermal conductivity of the thermal insulation layer is smaller than the thermal conductivity of the row tube. 
     
     
         5 . The heat exchanger capable of automatically defrosting or deicing according to  claim 1 , wherein the fins are symmetrically arranged on both sides of the row tube. 
     
     
         6 . The heat exchanger capable of automatically defrosting or deicing according to  claim 1 , wherein a plate surface of each of the fins is parallel to an axis of the row tube. 
     
     
         7 . The heat exchanger capable of automatically defrosting or deicing according to  claim 1 , wherein the thermal conductivity of the row tube is 5-500 W/(m·K); and/or
 the thermal conductivity of the first heat conducting part is 5-500 W/(m·K); and/or 
 the thermal conductivity of the second heat conducting part is 0.01-0.3 W/(m·K). 
 
     
     
         8 . The heat exchanger capable of automatically defrosting or deicing according to  claim 1 , wherein the row tube is made of copper, aluminum or stainless steel; and/or
 the first heat conducting part is made of copper, aluminum or stainless steel; and/or   the second heat conducting part is made of plastic or rubber.   
     
     
         9 . The heat exchanger capable of automatically defrosting or deicing according to  claim 4 , wherein the thermal conductivity of the thermal insulation layer is 0.01-0.3 W/(m·K). 
     
     
         10 . The heat exchanger capable of automatically defrosting or deicing according to  claim 4 , wherein the thermal insulation layer is made of plastic or rubber.