考虑壁面效应的摆动翼推进特性数值模拟

Numerical Investigation of Pitching Foil’s Propulsive Performance with Wall Effect

采用重叠网格技术对考虑壁面效应的摆动翼的推进特性进行数值模拟。系统地分析壁面距离、摆动运动幅值和无量纲频率f*对摆动翼推进特性的影响,并将其与自由流场中的摆动翼推进结果相对比。研究结果表明,摆动翼的推力随着壁面距离的减小呈现出逐渐增大的趋势,且存在最佳壁面距离对应最大推进效率。此外,对不同壁面距离下摆动翼后方的涡流场结构进行分析,从流动机理的角度对数值模拟结果进行解释。

A numerical investigation on the propulsive performance of a pitching foil with wall effect is performed in this study by using overlapping grid method.The systematic analysis upon the pitching foil’s propulsive performance under different wall distances,pitching amplitudes and non-dimensional frequencies f*are carried out.The numerical results show that the pitching foil’s propulsive force is increased with the decrease of wall distance,and the optimum wall distance leads to the highest propulsive efficiency.Moreover,the vortex structures behind the pitching foil under various wall distances are analyzed,providing explanation for the obtained numerical results from the perspective of flow mechanism.