泵喷推进器间隙流场尺度效应数值研究

Numerical Study of Scale Effects of Tip Clearance Flow Field of Pump-Jet Propulsor

由于泵喷推进器转子与导管之间有间隙的存在,内流场特性较复杂.为了探究尺度效应对泵喷推进器间隙流场的影响,采用非定常雷诺平均Navier-Stokes(URANS)方程和SST k-ω湍流模型,利用全结构化网格对计算域进行离散处理,滑移网格用于处理转子和其他部件之间的相对运动.首先通过网格不确定分析来验证本文数值方法的可行性,数值计算结果与模型试验数据进行了比较,两者吻合良好;然后对3种尺度泵喷推进器模型的敞水性能进行了数值计算,从涡量场和压力场的角度进行了分析.结果表明,全进速系数下,实尺度模型的效率会提高;实尺度模型的叶梢泄漏涡(TLV)涡量溃灭提前,涡量强度更低,并且TLV涡核中心压力系数更小,间隙间的脉动压力幅值更低.

Due to the tip clearance of the pump-jet propulsor(PJP),the flow field characteristics in the PJP are more complicated.To explore the influence of scale effects on the tip clearance flow field of PJP,the unsteady Reynolds-averaged Navier-Stokes(URANS)equation and the SST k-αturbulence model are used.The computational domain is discretized by structured grid,and the sliding grid is used to deal with the relative motion between the rotor and stationary components.The feasibility of the numerical method is verified by grid uncertainty analysis,and the numerical results are in good agreement with the model-scale PJP experimental data.The open water performance of the three scale PJP models is numerically calculated and analyzed from the perspective of vorticity field and pressure field.The results show that the efficiency of the full-scale PJP model will be improved under all the advance coefficients,the vorticity collapse of the full-scale PJP is earlier,the intensity is lower,the pressure coefficient of the TLV vortex core center is smaller,and the fluctuating pressure amplitude between the tip clearance is lower.