The Experimental Study of Condensation of R-134a inside Microfin Tubes

摘要

Microfin tubes are widely used in automobile refrigerant system and air conditioner equipment. This paper shows the test results for condensation of R-134A inside the 3/8″ diameter micro-fin tubes. The data were taken at fixed mass flow rate and heat flux for incremental changes in inlet vapor quality. Those data yield graphs of h and dp/dz vs. vapor quality for the three flow rates. The average vapor quality in the test section will span 0.2 to 0.90. Condensation data have been compared among single groove tube, cross groove tube and plain tube. Surprisingly, the cross groove tube shows lower condensation coefficient than does the helical single grooved tube.