An Experimental Comparison of the Refrigerant Flow through Adiabatic and Non-Adiabatic Helical Capillary Tubes

摘要

This paper presents experimental comparison of the R134a flow through lateral coiled capillary tubes-suction line heat exchanger (diabatic) and adiabatic coiled capillary tubes in vapor compression refrigeration cycle (VCRC). The experimental results illustrated that mass flux ratio (G_c/G_s) is main parameter that affects metastable flow through non-adiabatic coiled capillary tube. Therefore, an increase of the mass flux ratio represents a decrease of the heat transfer rate between the capillary tube and suction line. The measured and saturated pressure distribution also proof that metastable flow in the non-adiabatic coiled capillary tube with 1.397 mm inner diameter, 30 mm coil diameter, 4360 mm length, 4 mm inner diameter of suction tube exists, when the heat transfer rate between the coiled capillary tube and the suction line is weak with mass flux ratio more than 343.