Abstract: In order to show the physical mechanism of stationary wave in liquid swirl injector,the equal relation of surface wave phase speed and mean axial velocity at the nozzle part was analyzed based on existing theories.Numerical simulations of the two phase flow field in liquid swirl injector were carried on by solving the Navier-Stokes equations coupled with the VOF equation using CICSAM surface tracking technique on adapted grids in a long-nozzle axi-symmetric swirl model.Spatial stationary surface waves were caught in different backpressure conditions.By analogy with the classical gravity wave theories,the numerical results showed that the phase speed of surface wave and the mean axial velocity of liquid in the nozzle were equal and opposite in direction.The waves were generated by the steps of the transition part.The velocities of the energy propagation were smaller than the wave phase speed and this made the wave patterns show behind the step.

Key words: Hydrojet engine;Centrifugal injector;Stationary wave pattern+;Surface wave;Centrifugal wave+

摘要： 为了探讨液体离心喷嘴中静态空间波动现象的物理本质,在经典理论的基础上分析了液体离心喷嘴中喷口处表面波的相速度和平均轴向速度的相等关系,通过结合CICSAM表面捕捉技术在自适应网格中求解耦合VOF方程的N-S方程组的数值模拟,在旋转轴对称的长喷口模型中获得了不同背压下的空间静止波型。数值模拟结果与经典重力波理论的类比表明:表面波有与液体平均轴向速度大小相等方向相反的相速度;波动由喷嘴的过渡段台阶激励起;波动能量传播速度小于相速度使波动在台阶后的喷口段显现。

关键词: 液体喷射发动机;离心喷嘴;静态波形+;表面波;离心力波+