A Differential Pressure Technique for Void Fraction Measurement in Gas-Liquid Flow

Abstract

Two-phase Gas-liquid flows have many industrial uses, such as hydrocarbon transportation and energy production. The knowledge and an accurate determination of the gas phase's proportion rate in the two-phase mixture known as the gas void fraction is necessary for optimal and secure sizing of the installations where this kind of flow takes place. This paper focuses on the possibility of using a cost-effective differential pressure transmitter to measure the void fraction parameter. It is obtained using a mathematical model derived from the energy balance equation and the measured pressure drop from the vertical upward gas-liquid flow. Results on flow void fraction obtained through the use of the conductance probe method, are used to validate those derived from the pressure drop that is evaluated by employing the differential pressure transmitter. The measurement accuracy of the void fraction measured using the pressure drop technique, is found to be principally affected by the flow pattern. Moreover, the slip ratio between the phases was the primary factor influencing the void fraction measurement by the differential pressure technique.

Keywords

• two-phase flow
• void fraction
• flow pattern
• differential pressure
• transmitter