气液两相流混合模型代数重构方法

Algebraic reconstruction method for gas-liquid two-phase mixture flows

  • 摘要: 为提高国家数值风洞工程气液两相流软件混合模型求解器的自由界面模拟分辨率,增强多介质流体界面问题的模拟能力,基于代数重构方法,应用双曲正切函数界面捕捉格式对体积分数进行了插值重构,实现两相流混合模型与自由界面代数重构方法的耦合,抑制原混合模型下自由界面的非物理耗散现象,保持界面清晰尖锐;引入预处理技术,解决低速流动中由于特征值量级差距导致的计算刚性问题,提高收敛速度;应用双时间进行非定常时间推进。最后,采用方块对流、Zalesak盘刚性旋转和溃坝算例进行考核验证,数值结果显示,耦合了双曲正切函数界面捕捉格式的两相流混合模型在保持质量守恒的同时,获得了更高的自由界面分辨率,以及更丰富的多相流动细节。

     

    Abstract: To improve the resolution of interface capturing and enhance the ability to solve multi-fluid flows problems with MixtureSolver in gas-liquid two-phase flows simulation software of National Numerical Wind tunnel project (NNW-GLOWS). THINC (Tangent of Hyperbola for INterface Capturing) scheme is applied to compute the numerical flux for the volume fraction function. The coupling of mixture solver with algebraic reconstruction method prevent the unphysical dissipation and maintain sharp fluid interface. Meanwhile, precondition technique is adopted to shrink the convergence course by avoiding imbalance of eigenvalues in low speed flows. Dual-time stepping is applied for unsteady time-marching method. Finally, square advection, Zalesak’s disk solid rotation, and dam break are tested, the numerical results demonstrate that the mixture model solver coupled with THINC approach possess higher resolution for interface capturing and more details in flow field details on the premise of maintaining the conservation of components.

     

/

返回文章
返回