悬停共轴双旋翼干扰流动数值模拟

基于非结构动态嵌套网格方法,通过求解三维非定常Euler方程对悬停共轴双旋翼直升机的复杂流场进行了数值模拟研究.双旋翼之间的干扰使得两者的拉力性能下降,上旋翼对下旋翼的干扰程度远大于下旋翼对上旋翼的影响程度.下旋翼处的下洗速度比单旋翼的要大得多,而上旋翼的下洗速度比单旋翼的略大一些,几乎相同.桨叶总星巨角增加,则下洗速...

Numerical simulation of interaction unsteady flows around co-axial rotors in hover

Numerical simulation of three-dimensional(3-D)unsteady Euler equations was conducted to investigate the unsteady flows around co-axial rotors in hover.The thrust performances of two rotors became worse because of the interaction between them,and the influence of the upper rotor on the lower rotor was greater than that of the lower rotor on the upper rotor.The downwash velocity at the lower rotor plane was much larger than that at an isolated rotor plane,and the downwash velocity at the upper rotor plane was a little larger than that at an isolated rotor plane.The downwash velocity and thrust coefficient became larger when the collective angle of blades was added.With the increase of distance between the two co-axial rotors,the thrust coefficient of the upper rotor increased,and the total thrust coefficient reduced,because the thrust coefficient of the lower rotor dropped greater than the increment of the upper rotor.