气液两相流瞬变流数值模拟研究

Study on the Numerical Simulation of Transient Flow of Gas-Liquid Two-phase Flow

根据双流体模型建立了气液两相流瞬态水力学模型,对数学模型进行了特征化分析,利用模型方程的特征值和左特征向量将偏微分方程组转化为常微分方程组。以预估-校正法为基础,采用差分特征线算法进行数值求解,并编制了相应的程序。在大型多相流试验环道上进行了气量快速增加和减小的试验,计算值与试验值的比较结果表明,算法的收敛性和稳定性很好,程序较好地预测了气相流量瞬变过程中的压力和含气率的变化,能够分析瞬态流动过程中各参数的变化。

A transient hydrodynamic model of two-phase flow is established according to two-fluid model. The system of governing equations is proved to be well posed by means of characteristic analysis. With eigenvalues and left-eigenvectors derived from the model equations, the partial differential equations are transformed into ordinary differential equations. The characteristic line scheme based on preliminary estimate and correction difference is adopted for numerical simulation and corresponding programs are made. Experiments of rapid increased and decrease of flow rate of gas phases are conducted on large multiphase test loop of 80 mm ID and 380 m in length. Comparisons of calculation and experiments demonstrate that the scheme achieves good convergence and stability and the programs make good prediction of pressure and void fraction in gas flow rate transients and are capable of analyzing various parameters in transient flow.