【摘要】 本文应用拟合坐标系和有限解析法分析计算二维管壁凸体的层流绕流。计算了台阶绕流的流速场,其结果与试验资料吻合。文中还预报了半圆柱凸体的绕流。发现分离点随雷诺数的增大而向上游移动,当Re>130时,分离点的位置不再改变。更多还原

【Abstract】 In this paper the boundary-fitted coordinate system is adapted to map the obstacles with arbitrary shape into a simple transformed plane with rectangular grid system. For upstream and downstream planes Neumann boundary conditions are used to keep the orthogonal grids near these boundaries. The finite analytic method which utilizes the local analytic solution of the partial differential equation is applied to predict the separated laminar flow past a wall-mounted obstacle in two-dimensional channel. For backward-facing step flow, the numerical results gives good agreement with experimental data. It is shown by the prediction of flows over semi circular obstacle that the point of separation moves upwards as the Reynolds number increases and becomes unchanged as Re>130.更多还原