ANALYSIS OF TWO-PHASE FLOW JET WITH COMPRESSIBLE TWO-PHASE TWO-FLUID CODE

摘要

Analysis of compressible gas-liquid two-phase flow is important for safety and reliability assessment in nuclear engineering and other industrial fields. A new numerical method for the compressible two-fluid model is developed. Solution of the Riemann problem, which is necessary to treat the relationship between discontinuities of pressure and velocity in highly compressible flow, is introduced to the two-fluid model calculation. Two-phase volumetric velocity and mixture sound speed are adopted in the Godunov Scheme for solving the Riemann problem in two-phase flow. This technique is employed in the finite volume method for two-fluid model calculations and the calculated speed of sound is in good agreement with the theoretical one. The present method is applied to analysis of an experiment of supersonic steam-water two-phase jet impingement. The predicted peak pressure on the target plate is 10% smaller than the observation. The difference between predicted and observed peak pressures is small enough to allow application of the method to assess nuclear safety, but evaluation of phase change rate should be improved for more accurate predictions.