FLOW PATTERN AND VOID FRACTION OF REFRIGERANT TWO-PHASE FLOW IN A HORIZONTAL PIPE.

Abstract

Refrigerants used were R12 and R22, and the saturation pressure range was from 5. 7 to 19. 6 bar. From obtained data it was found that the flow pattern of the refrigerant two-phase flow can be presented on a revised Baker map, where the property correction factor on surface tension was modified. It was also found that the influence of the shut-off speed in void fraction measurement is negligible. Experimental data on void fraction agree well with Zivi, Thom and Baroczy correlations approximated by Butterworth.