中文摘要：

把无网格/直角网格混合算法发展用于涉及动边界的非定常流动计算问题。采用无网格/直角网格混合算法,计算区域整体采用直角网格,只在物面附近嵌入局部无网格。对于动边界问题,本文让主体直角网格保持固定,用原混合算法中的局部无网格区跟随运动边界,使得动边界物面附近有不变的点云结构,避免了点云重构;无网格区与直角网格交界面随边界运动跟踪确定,由于主体基于直角网格,方便了交界面的跟踪。用发展的混合算法,结合非定常Euler方程双时间推进方法,先对翼型作俯仰振荡的非定常跨声速流动进行了数值模拟,计算结果与现有文献和实验数据进行了比较与验证;结合刚体运动方程,成功模拟了二维外挂物投放过程,算例展示出发展的混合算法适合处理大位移运动边界问题。

英文摘要：

The hybrid cartesian grid/gridless method is advanced for solving moving boundary problems.In the present method,the moving body is enveloped by a cloud of gridless points,for following the motion of the body against a background of cartesian grids.The topology of the gridless clouds is unchange so that the cloud regeneration can be avoided;As the flow field is basically discretized by cartesian grids,the interface between the gridless region and the cartesian grid can be traced.Coupled with a dual time-stepping method,the resulting hybrid method is implemented to solve two-dimensional unsteady compressible Euler equations.The flow past a pitching airfoil harmonically about the quarter chord is firstly simulated.Numerical results are in good agreement with experimental data.Then,the store separation from a wing section is simulated.The result shows that the hybrid method can handle the unsteady flow problems involving large-scale moving boundaries.