具有运动边界不可压缩黏性流动的CBS有限元解法

A Characteristic-Based Split-FEM Scheme for Incompressible Viscous Flow with Moving Boundaries

基于特征分裂(CBS)算法,提出了一种适用于具有运动边界的不可压缩黏性流动问题的有限元解法,给出了不可压缩黏性流动问题的控制方程,并推导了其无量纲形式.将传统CBS算法与动网格技术相结合,提出了一种动边界流动问题的求解流程,并对所采用的基于弹簧近似的动网格方法进行了说明.采用该方法对静水和均匀来流中的简谐振动圆柱绕流问题进行了求解,计算所得圆柱受力、圆柱表面压力和涡量分布以及流场速度分布等结果均与已有数值或实验结果相吻合,初步验证了所提方法的可行性.

A characteristic based split （CBS）-FEM scheme for the incompressible viscous flow with moving boundaries was proposed, including the governing equations established and the cor- responding non-dimensional equations deduced. Moreover, combined the conventional CBS algo- rithm with the mesh moving technique, a solution procedure in Eulerian coordinates was obtained and the spring analogy-based mesh moving technique was discussed. In addition, the proposed method was applied to two flow problems, i.e. the flow induced by the harmonic oscillating circular cylinder in water at rest, and the uniform flow around a transversely oscillating circuZar cylinder. The numerical results such as the drag and lift forces of the cylinder, the pressure and vorticity on the cylinder surface, and the velocity distribution of the flow field agree well with the numerical and experimental results in literatures.