Condensation and evaporation heat transfer characteristics of pure and binary-mixture HFO refrigerants inside a plate heat exchanger

摘要

In the present study, condensation and evaporation local heat transfer coefficients and pressuredrop of the pure and binary-mixture HFO refrigerants inside a brazed plate heat exchanger wereinvestigated by using a test section which is combined with two grooved stainless steel plates. In thetest section, wall temperature distribution was measured for local heat transfer coefficient. In orderto measure local heat transfer and temperature distribution, five thermocouples were set on flowdirection for each wall temperature measurement of the refrigerant side and heat source water side.Local heat transfer coefficient were calculated from local wall temperature of refrigerant side,saturation temperature and local heat flux obtained by temperature gradient between heat transfersurface of refrigerant side and heat source side.