Three-Phase Flow Tomography System in Upward-Vertical High-Viscous-Oil/Water/Gas Flow

Abstract

A new three-phase flow tomography system is presented in this work. The system was developed to be applied in high-viscous-oil/water/gas flow arranged in different flow patterns, with the three fluids present simultaneously in a crossing point. The primary measurement is based on a simpler and reliable digital in-phase/quadrature (IQ) demodulator and a wire-mesh sensor (WMS), but the system is capable of including different types of primary measurements. Dynamic three-phase flow tests were carried out to verify the system performance and compare its results with the ones obtained by quick-closing valves (QCVs) and a high-speed video camera. <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">In situ</i> volumetric fractions and flow patterns were compared. The experiments were conducted in a vertical glass pipe of 50-mm i.d. and 12-m height. The observed three-phase flow patterns were water-continuous churn flow with dispersed bubbles and oil drops (WChBoDo), water-continuous slug flow with Taylor bubbles, spherical bubbles, and oil drops (WPiBoDo), and oil-continuous slug flow with Taylor bubbles, spherical bubbles, and water drops (OPiBoDi). Compared with the measurements using QCVs, the average relative errors of the measured volumetric phase fractions were 12% for water, 13% for air, and 22% for oil. The experimental results, including the details of the flow inside the pipe, the phase distributions, and the objective characterization of flow patterns, suggest that the proposed system is a promising option for three-phase flow-related studies and developments. The proposed technique can reach 8930 frames/s with a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$16\times16$ </tex-math></inline-formula> WMS.