The structure of gas–liquid flow in a horizontal pipe with abrupt area contraction

Abstract

Single fiber optical probes were used to measure the cross-sectional void fraction distribution for air–water flow in a horizontal test section with sudden area contraction. The local void fraction was plotted as a function of its two spatial co-ordinates, so that a representation of the time average gas distribution over the cross-section could be obtained. The cross-sectional average void fraction was obtained by numerical integration of the local values; the contraction was shown to considerably alter the distribution of the phases, so that the correlations for straight pipes appear no longer suitable.