THREE-DIMENSIONAL SIMULATIONS OF LIQUID-GAS FLOWS AT THE NEAT-PETROBRAS TEST LOOP FOR CALIBRATION OF AN ULTRASONIC MULTIPHASE FLOW METER

The present paper describes the CFD numerical simulations of liquid-gas flows in the test rig at Nucleo Experimental de Atalaia (NEAT-PETROBRAS). Results for three flow patterns are presented and discussed: plug flow, slug flow, and stratified wavy flow. In addition, flow pattern transitions were determined based on the CFD results. The simulation results provided relevant information about the flow patterns as well as the transitions between them. Except for the annular flow, which presents several difficulties for simulation, the flow pattern predictions in the simulations agree with the predictions made using the Baker flow pattern map. Furthermore, the CFD simulations allowed for reliable, time dependent GVF results, which can be used for direct comparison with the acoustic signals from the multiphase flow meter. The CFD simulations described herein thus provide the necessary means for calibration of the ultrasonic multiphase flow meter being developed.