Experimental Study on Heat Transfer Performance of Antiseptic Evaporator

Abstract

Corrosion is the problem which geothermal source heat pump system must face and resolve. In this paper, heat transfer characteristic of one kind of antiseptic evaporator was tested. Antiseptic dope was spray-painted onto the surface of water channel of the evaporator to help fight corrosion. While, antiseptic coating would add heat resistance of the evaporator. Experimental research was carried out to study the effect of antiseptic coating on heat transfer characteristic of the evaporator. In the condition of different water velocity and temperature, heat transfer performance of spray-painted antiseptic U-type double pipe evaporator and unpainted U-type double pipe evaporator were tested and contrasted. It indicated that when water velocity is less and in laminar flow, heat transfer coefficient of the spray-painted antiseptic evaporator is larger than that of the non spray-painted evaporator, which is because the surface roughness of coating enhanced convection heat transfer coefficient. While when water velocity is large and in turbulence flow, the enhancement of coating surface roughness is weaken, then the heat transfer coefficient of the spray-painted antiseptic evaporator is less than that of the non spray-painted evaporator.