三维可压缩水气混合物射流冲击平板特性研究

根据质量和动量守恒方程,忽略流体的粘性,计入流体的可压缩性,建立水气混合物射流冲击平板问题的物理模型.采用内域双渐进方法对控制方程进行数值离散,平板边界和水域分别进行处理以满足各自的边界条件.数值结果与解析解及Autodyn的数值结果吻合较好.在验证方法合理性的基础上,深入地分析了含气量对射流冲击载荷特性的影响规律.数值结果表明:随着含气量的增加,冲击压力峰值将会显著地降低,而脉宽和射流冲击压力的极小值都会增大.

Three-Dimensional Problem of the Compressible Water-gas Mixture Impacting on Rigid Plates

On the basis of the mass and momentum conservation, an inviscid model is established to investigate water-gas mixture impact problems, for which weak compressibility should be taken into consideration. The Internal Doubly Asymptotic Approximation method is adopted to solve the govern-ing equation. A separate treatment on the free surface and rigid plate is used to satisfy the boundary conditions. The numerical results are in excellent agreement with those calculated by the Autodyn solver and the corresponding theoretical formula. The influence of volume fractions of gas on the im-pact load characteristics is investigated. The results reveal that with the volume fraction of gas in-creasing, the peak of load will decrease significantly. Meanwhile, the pulse width and the minimum value of the pressure will increase for homogeneous water-gas mixture impact.