Research on Application of Lagrangian Direct Numerical Simulation to the Unsteady Incomprssible Viscous Flow with Moving boundary.

在本研究中，通过引入运动边界条件，将先进的涡旋方法推广到围绕振动边界或运动边界的非定常不可压缩粘性流动的分析中。通过对受迫振荡圆柱绕流的仿真，验证了该计算方法的有效性。计算结果与实验结果吻合较好，包括作用在柱体上的非定常流体力、典型流型、尾迹涡结构和闭锁现象。将该仿真技术应用于自由振荡圆柱体周围流动、振荡翼型流动和离心泵叶轮流动的非定常特性分析。结果表明，带运动边界条件的先进涡旋法是研究运动边界绕流和流激振动问题的有效工具之一。在水箱中对受迫振荡圆柱的流动进行了实验研究。对典型的流型、涡结构进行了可视化，并测量了非定常流动力。

In this research, the advanced vortex method was extended to the analysis of unsteady incompressible viscous flow around oscilating or moving boundaries by introducing the moving boundary condition. The validity of the calculation technique presented here was examined by the simulation of flow around a forced oscillating circular cylinder. The calculation results, such as unsteady fluid force acting on the cylinder and typical flow patterns, vortex structures in the wake and lock-in phenomena were in good agreement with those of experiments. The simulation technique was also applied to the analysis of flow around an freely oscillating circular cylinder, an oscillating airfoil, and unsteady characteristics of flows through a centrifugal-pump impeller. It is confirmed that the advanced vortex method with moving boundary condition is one of the efficient tool of the research on flow around moving boundary and flow induced vbration problems.The flow around a forced oscillating circular cylinder was investigated experimentally in a water tank. The typical flow patterns, vortex structures were visualized and unsteady fluid forces were measured.