LAUSR

ABSTRACT Numerical studies on straight and spiral capillary tubes are addressed for the CO2 and R22 refrigerant. A homogenous, one-dimensional steady-state adiabatic flow model is developed using fundamental principles of fluid dynamics and thermodynamics. Churchill and Ju et al. friction factor correlations are employed. Numerical results are validated with the experimental results of Agrawal and Battacharya, Jabaraj et al. and Mittal et al. For similar operating conditions, the mass flow rate and length of the tube are significantly larger in the case of CO2 refrigerant. A reduction in mass flow rate in the spiral capillary tube is about 22% and 15% compared to the straight capillary tube with CO2 and R22 refrigerants, respectively.