Gamma Densitometry Measurements of Gas/ Liquid Flow with Low Liquid Fractions in Horizontal and Inclined Pipes

The ability to accurately predict the volume fraction of different phases flowing in a pipe is of extreme importance to nuclear and oil industries, among others. This article will focus on the application of a single-beam gamma densitometer to investigate gas/liquid flows with low liquid fractions in horizontal and inclined pipes. The experiments are performed in a 15 m long, 56 mm diameter, inclinable stainless steel pipe using Exxsol D60 oil (viscosity 1.30 mPa s, density 793 kg/m3), water (viscosity 0.89 mPa s, density 999 kg/m3) and air (viscosity 0.018 mPa s, density 1.22 kg/m3) as test fluids. The test pipe inclination is changed in the range from 5º upward to 5º downward. Experimental measurements are reported at three different mixture velocities, 5, 10 and 15 m/s, and the inlet liquid fraction is varied from 0.0010 to 0.0100. In the experiments, the vertical interface position is measured by traversing horizontal gamma beams, and the curvature of the interface is measured by traversing vertical and angular gamma beams.