两流体双压力模型半隐数值算法研究

Study on Semi-Implicit Scheme for Two-Fluid Seven-Equation Two-Pressure Model

目前主流的系统分析程序都是基于经典两流体六方程单压力模型开发而来的。然而这种模型是不适定的,严重降低了程序的数值稳定性。两流体七方程双压力模型具有无条件完全适定的性质,本文研究了这种模型的半隐数值解法,并采用两相沉降问题、水龙头问题和爱德华喷放问题进行验证。数值结果表明,该算法在模拟核工程领域重要两相流问题时,具有较高的稳定性和准确性。

Current main reactor thermal-hydraulics system analysis codes are developed based on two-fluid six-equation single pressure model. However, such six-equation model has been proved to be ill posed, which could lead to numerical oscillations. Since two-fluid seven-equation two-pressure model is unconditionally well-posed in all situations, a semi-implicit algorithm based on the finite volume method with staggered grids is developed to solve such well-posed two-pressure model. Then the algorithm is validated on two-phase sedimentation test, water faucet test, and Edwards blowdown experiment. The calculation results show that the proposed numerical algorithm is accurate and robust in solving two-phase flows in the field of nuclear engineering applications.