Analysis of a meshless solver for high Reynolds number flow

作者：Su Xinrong^*; Yamamoto Satoru; Nakahashi Kazuhiro

来源：International Journal for Numerical Methods in Fluids, 2013, 72(5): 505-527.

DOI：10.1002/fld.3747

• meshless solver
• high Reynolds number flow
• accuracy
• misalignment effect
• aspect ratio
• curvature

In this paper, the extension of an upwind least-square based meshless solver to high Reynolds number flow is explored, and the properties of the meshless solver are analyzed both theoretically and numerically. Existing works have verified the meshless solver mostly with inviscid flows and low Reynolds number flows, and in this work, we are interested in the behavior of the meshless solver for high Reynolds number flow, especially in the near-wall region. With both theoretical and numerical analysis, the effects of two parameters on the meshless solver are identified. The first one is the misalignment effect caused by the significantly skewed supporting points, and it is found that the meshless solver still yields accurate prediction. It is a very interesting property and is opposite to the median-dual control volume based vertex-centered finite volume method, which is known to give degraded result with stretched triangular/tetrahedral cells in the near-wall region. The second parameter is the curvature, and according to theoretical analysis, it is found in the region with both large aspect ratio and curvature, and the streamwise residual is less affected; however, the wall-normal counterpart suffers from accuracy degradation. In this paper, an improved method that uses a meshless solver for the streamwise residual and finite difference for wall-normal residual is developed. This method is proved to be less sensitive to the curvature and provides improved accuracy. This work presents an understanding of the meshless solver for high Reynolds number flow computation, and the analysis in this paper is verified with a series of numerical experiments.

• 出版日期2013-6-20