Refrigerant R-22 with a mass flow rate of m = 8.75 X 10-3 kg/s is condensed inside a 7-mm-diameter tube. Annular flow is observed. The saturation temperature of the pressurized refrigerant is Tsat = 45°C, and the wall temperature is Ts = 40°C. Vapor properties are pv = 77 kg/m3 and µ,v = 15 X 10-6 N · s/m2.
(a) Determine the heat transfer coefficient and the heat transfer and condensation rates per unit length at a quality of X = 0.5.
(b) Plot the condensation rate per unit length over the range 0.2 X 0.8.