气液两相管流水力瞬变的数值计算及实验研究

Numerical and Experimental Investigation to Gas-Liquid Transient Pipeline Flow

由气液两相管流的基本方程出发,通过引入矢通量分裂,对传统的特征线差分做了较大的改进,形成了基于矢通量分裂的特征线差分解法。该法首先将控制方程组的特征值分解成正、负两部分,进而将控制方程中的矢通量雅可比矩阵分裂成两个亚矢量矩阵,对其按各自的迎风格式差分,从而建立了稳定的差分求解格式。该计算法适合于计算声速变化较大且计及液流速度的气液管流的瞬变。计算求解得到的各种不同初始空隙比的压力变化曲线、声速曲线、波速变化曲线、空隙比变化曲线及气体释放影响曲线,通过与不同初始空隙比时气液管流水力瞬变的实验结果对比分析,结果表明两者吻合较好,说明本文方法对于低空隙比的气液两相管流具有较普遍的适用性。

Based on the equations of two-phase transient flow,the traditional characteristic method is improved via introducing the flux vector splitting to form the flux vector splitting algorithm,where the characteristic values of the controlling equations are separated into two parts,then the flux vector splitting Jacobian matrices is separated into two vector matrices,and the difference equation is solved respectively according to one of the calculation forms.This proposed algorithm especially is adopted to evaluate the two-phase transient flow with great sound speed variation.The pressure curves of different initial void fraction,sound-speed curve,wave-speed curve,void fraction waving curve are obtained.A comparision between the simulated and experimental results of different initial void fraction of two-phase transient flow indicates the common adaptability for two-phase transient flow with low void fraction.