Experimental Study and CFD Simulation of Two-phase Flow Measurement Using Orifice Flow Meter

Due to the importance of measuring multiphase flows in the oil, gas, refining and petrochemical industries, in this study, the feasibility of different two-phase flow measurement methods has been investigated. Two-phase flow loop and measurement equipment including orifice plate flow meter and mercury manometer have been designed according to the international standards. Flow rates of water and air phases in two-phase flow loop have been measured using electromagnetic and turbine flow meters respectively before entering the mixing section and forming two-phase flow. Total mass flow rate of two-phase flow passing through the orifice flow meter has been equal to the total mass flow rate of water plus the total mass flow rate of air that has been measured by electromagnetic and turbine flow meters respectively. The orifice pressure drop for different flow rates of water and air and various volume fractions of air in two-phase flow has been measured. Reynolds number and air volume fraction of two-phase flow were in the range 744 – 10000 and 15 – 40% respectively. Effects of Reynolds number and air volume fraction of two-phase flow on the orifice plate performance have been investigated. For low Reynolds numbers of two-phase flow that the plug flow pattern has been dominant, the slope of changes for discharge coefficient has been more in comparison with upper ranges of Reynolds number where the flow pattern is changed from plug flow to stratified. Orifice plate flow meter has been simulated using CFD approach. The standard K-Epsilon turbulence model has predicted better results than other turbulence models. The present study provides the basis for measuring two-phase flows in the oil and gas industry.