轴对称底部姿控喷流干扰流场的Navier-Stokes数值模拟

THE NAVIER-STOKES SIMULATION FOR INTERACTION OF ATTITUDE CONTROL JET AT BASE WITH A SUPERSONIC AXISYMMETRIC FLOW

本文应用MacCormack显格式对超音速锥形弹头轴对称底部姿控喷流干扰流场进行了数值模拟。对Baldwin-Lomax代数湍流模型根据底部流的特点进行了修正。用椭圆型偏微分方程法生成了能在壁面、喷口和台阶肩部附近局部加密的网格。计算表明带横向喷流的超音速底部流动由于喷流与来流的强干扰和底部流动本身的复杂性使得网格生成和湍流模型对数值解的影响很大。从依据计算结果画出的全流场速度向量图能清楚地观察到流动的分离现象。给出了有喷流和无喷流情形下的壁面压力分布和底部阻力系数,并对二者进行了比较分析。

In this paper, time dependent Mac Cormack explicit scheme is used for the numerical simulation of axisymmertric flow interacted with attitude control jet at the base of a conical missile. Baldwin-Lomax algebraic turbulent model is corrected to adapt the feature of the base flow. The grids generated by using elliptic P.C.E method can cluster near the wall, the slot and the shoulder of the step. It is shown the grid generation and turbulent model have great influence on the accuracy of the solution of a supersonic base flow with transverse jets because of the strong interaction between the jets and the main stream and the inherent complexity associated with base flow. The flow separation phenomena can be clearly observed from the computed velocity vector field. The pressure distribution and the drag coefficients of the base are given for the cases with and without jet and the results of the two cases are compared to each other.