自主推进俯仰震荡翼型的数值模拟研究

运用自适应多重网格法和内置边条法研究了俯仰震荡翼型的运动.通过研究翼型的原地摆动与自由游动,提出了一种确定自主推进俯仰震荡翼型推力的方法,得到了推力系数、功率系数和推进效率与Strouhal数的关系.与以往研究不同的是,我们还得到了Strouhal数随雷诺数的变化规律.此外,从自由游动翼型诱导出的涡量场中可以清楚的观察到旋涡的合并,这与实验研究非常吻合.

NUMERICAL SIMULATION OF SELF-PROPELLED OSCILLATING FOIL

A self-propelled oscillating foil is investigated.The 2D incompressible Navier-Stokes equations are solved by multigrid method with adaptive mesh refinement,and the moving boundary is handled with the immersed boundary method.To get the thrust of a self-propelled oscillating foil,a new method is raised,by which the thrust and the self-propelled speed are obtained by investigating the tethered oscillating foil and the self-propelled oscillating foil,respectively.Then,the Strouhal number,the thrust coefficient,the power coefficient,the propulsive efficiency and the relationship among them are obtained.The relationship between the Strouhal number and the Reynolds number is first obtained by our numerical study.In addition,we studied the process of vertex control in the wake of self-propelled oscillating foil which is coincide with the observation in other's experiments.