定转子间距对泵喷推进器的影响

Influence of Constant Rotor Spacing on Pump-jet Thrusters

摘要:

采用计算流体力学(Computational fluid dynamics，CFD)的方法，计算 3 种不同定转子间距的泵喷推进器模型，探究了定转子间距对泵喷推进器的推进性能及流场的特性影响。结果表明：定转子间距主要影响其扭矩平衡的效果，间距越大扭矩平衡效果越差；随着进速系数的增加，后置定子的扭矩会超过转子扭矩，使泵喷推进器处于“超平衡”状态；分析了定转子间的切向和径向速度场的分布特性，以及转子表面压力分布特性；后置定子上下表面的压力差，是其产生扭矩的主要原因，定转子压力差在定子的中间部分达到最大；定子的上下表面压力差随着间距的增加而减小。采用粒子图像测速(Particle image velocimetry，PIV) 实验方法验证了数值模拟方法的准确性，研究结果可为泵喷推进器的设计及其流场特性分析提供基础。

Abstract:

This paper uses computational fluid dynamics(CFD)method to calculate three pump-jet thruster models with different fixed rotor spacing，and explores the influence of fixed rotor spacing on the propulsion performance and flow field characteristics of pump-jet thruster. The results show that the constant rotor spacing mainly affects the torque balance effect，and the greater the rotor spacing，the worse the torque balance effect. With the increase of the speed coefficient，the torque of the rear stator will exceed the torque of the rotor，making the pump-jet propeller in the state of “overbalance”. The distribution characteristics of tangential and radial velocity fields between fixed rotors and the distribution characteristics of rotor surface pressure are analyzed. The pressure difference between the upper and lower surfaces of the rear stator is the main reason for its torque，and the pressure difference between the fixed rotor reaches the maximum in the middle part of the stator. The pressure difference between the upper and lower surfaces of the stator decreases with the increase of the spacing. Particle image velocimetry(PIV)experiment is used to verify the accuracy of the numerical simulation method. The results of this paper can provide a basis for the design of pump-jet thrusters and the analysis of flow field characteristics.