水下亚声速细长锥型射弹超空泡流的数值计算方法

采用理想可压缩流体无旋定常流动及超空泡尾部Riabushinsky闭合方式假定,基于水动力学势流理论及细长体理论,建立了描述水下亚声速条件下细长锥型射弹超空泡流动的积分微分方程。发展了求解该方程的数值离散方法,提出多种超空泡外形初始解,分析了它们对超空泡形态计算结果的影响,优化了计算过程,简化了初始迭代条件。分析了流体压缩性对超空泡流动参数的影响,当马赫数大于0.3时,超空泡外形、射弹表面压力系数及射弹运动压差阻力系数均明显增大。计算得到的超空泡流动参数与相关文献的理论和实验结果吻合良好。

Numerical method of supercaviting flow past a slender cone type projectile traveling in water at subsonic speed

On the assumption that the ideal compressible fluid motion is irrotational and steady,supercavitating closure with the Riabushinsky scheme.An integro-differential equation for the supercavitating flow past a slender cone type projectile traveling in water at subsonic speed is derived based on the potential flow theory of hydrodynamics and the slender body theory.A numerical discrete method for solution of the integro-differential equation is developed,various initial solutions of supercavity profile are proposed and the influence on results are analyzed.The process of computation is optimized and the initial cavity solution for the first iteration is simplified.Compressibility influence of flow field on characteristic parameter of supercaviting flow is analyzed,while the Mach number exceeds 0.3,more remarkable increasement of supercavity shape and pressure coefficient on projectile surface and drag coefficient of projectile will occur.The calculated results about characteristic parameter of supercaviting flow are compared with relative theoretical and experimental ones,and a good agreement exists.