A PRESSURE-BASED TWO-PHASE FLOW METHOD FOR COMPUTATION OF BUBBLE CAVITATION FLOWS

摘要

A pressure-based two-phase flow method is proposed for computation of high-speed cavitation flows by coupling a Two-Fluids Three-Pressure bubble dynamics model and a compressible two-phase flow computation. The fluid mixture of two-phase media is composed of a liquid and spherical gas bubbles, those are supposed to disperse in the liquid phase uniformly. State equations of the liquid and gas phases are employed to relate their density with pressure, and the flow of two-phase mixture is then calculated by employing Navier-Stokes equations. Cavitation is evaluated by the volume fraction of gas phase and the average radius of cavitation bubbles in a local flow field is calculated by applying Rayleigh-Plesset equation. For simultaneous computation of above equations, a pressure-based predictor-corrector procedure is developed by applying CCUP method. As an example, flows in an orifice nozzle are treated and the reliability of computation is estimated by comparison with experimental data.