不同湍流模型下偏导射流伺服阀前置级流场特性仿真
Simulation on flow field characteristics of deflector jet servo valve pre-stage under different turbulence models

摘要 利用常用的k-ε湍流模型对偏导射流阀前置级流场进行数值模拟，探讨不同湍流模型对偏导射流伺服阀流场信息的影响.在相同初始条件下,对偏导射流阀前置级流场进行两相流二维数值计算,获得不同湍流模型下,压力、速度场信息及气穴分布特点.针对两接收腔压力仿真值比实测值要小的情况，主要是由于将流场边界层流动视为高雷诺数流动与实际情况不符造成,引入低雷诺数模型对边界层进行处理.在此模型的基础上继续深入研究单向流和两相流模型及不同背压和湍流强度对流场特性的影响.仿真结果表明:接收腔压力提高并与实测值相一致.采用两相流模型获得的结果更为真实,并且提高背压和增大湍流强度都会使两接收腔压力升高,对空化现象有一定的抑制作用.
Abstract：Common k-ε turbulence models are used to simulate the pre-stage flow field of the deflector jet valve and the influence of different turbulence models on the flow field information of the deflected jet servo valve is discussed. Under the same initial conditions, it carries out the pressure, velocity field information and distribution characteristics of cavitation in different turbulence models, however, the simulation value of two receiving cavity pressure is smaller than the measured value. Mainly due to regard the boundary layer flow as high Reynolds number flow, which is inconsistent with the actual situation. Therefore, the low Reynolds number model is introduced to deal with the boundary layer. In addition, the effects of unidirectional and two-phase flow models and the different backpressure and turbulence intensities on the flow field are studied based on this model. The results show that the pressure of receiving cavity is increased and consistent with the true value. The two-phase flow model is more realistic, and both the backpressure and the turbulence intensity increase will cause the pressure in the two receiving cavities to increase, and the cavitation phenomenon will be restrained to a certain extent.