Spatial distribution of oil and water in horizontal pipe flow

In this paper we report a series of experiments to quantify the spatial dis tribution and identify the flow pattern of liquid-liquid How in a horizonta l 25.4-mm (nominal 1-in.) tube. Experimental results are presented for kero sene (EXXOL D80) and tap water at room temperature. Two different measureme nt techniques (a high frequency impedance probe and a gamma densitometer sy stem) were applied for measuring the volume fraction distribution across th e tube and to obtain tomographic results for phase distribution. The use of the gamma densitometer system to obtain the tomographic results in liquid- liquid cocurrent flow is believed to be the first in this field. These meth ods are more precise than other techniques such as visualization and help t o distinguish certain differences in flow patterns for different superficia l velocities and liquid fractions. The two sets of measurements were compar ed and it was concluded that the gamma densitometer system was a more relia ble method by which to measure the volume fraction. Two important phenomena in liquid-liquid flow were observed: oil encapsulation by water at low mix ture velocity and droplets concentrated at the center of the pipe in the di spersed flow regime. Some possible explanations are given regarding these p henomena.