非共沸混合冷媒の水平溝付管内沸騰熱伝達と圧力損失 Boiling Heat Transfer and Pressure Drop of Non-Azeotropic Mixtures Inside a Horizontal Grooved Tube
The evaporation of HCFC141b, HFC152a and HFC23, and non-azeotropic refrigerant mixture used at the very low temperature refrigeration system is experimentally studied in a horizontal spirally grooved tube with corrugation.<br>The experiments were conducted at 0.03 to 0.47MPa of boiling pressure, 100 kg/(m<SUP>2</SUP>s) of mass flux, 1 to 15 kW/ m<SUP>2</SUP> of heat flux, -26 to 21 °C of refrigerant temperature and 11.4 mm of average inner diameter.<br>It is concluded that boiling heat transfer coefficients of single-refrigerant are higher than these of non-azeotropic refrigerant mixture. And dimensionless correlation of the heat transfer coefficirnts, i.e. Lockhart-Martinelli parameters agreed with equation (10) within the limit of ±40 percent. Pressure drops of these refrigerant mixture depend on its liquid density and flow pattern.
日本冷凍協会論文集 12(1), 53-62, 1995-03-31
Japan Society of Refrigerating and Air Conditioning Engineers