二维空化、超空化流动的数值模拟

A numerical simulation of the cavity,supercavity flow

通过引入混合密度函数发展了一种新的空化模型,运用Navier-Stokes方程加k-ε两方程湍流模型对Ep-pler E817和NACA 0015水翼的空化流动进行了数值模拟,得到了从空化到超空化的一系列变化过程的数值模拟结果。通过与实验数据进行对比,发现二者吻合较好。

Numerical simulation results of turbulent cavitating flow around two-dimensional hydrofoil were presented in this paper, in which the Navier-Stokes equations with k-ε two-equation turbulence model and the developed cavity model were used. In the present model, it is assumed that the fluid initially contains uniformly distributed small gas bubbles which will behave as described by the vapor transport equation in a changing pressure field. And the gas bubbles are included by prescribing an estimated mass fraction at the inlets. This value is held constant throughout the calculation domain. However, the corresponding density varies significantly with local pressure. To assess our numerical method, several cavity flows over the Eppler E817 hydrofoil were computed and the numerical results were compared with experimental results. It shows that the numerical results by the present cavity model agreed with the experimental results very well. Then, the wonderful phenomenons of cavity and supercavaty flows around the NACA0015 hydrofoil were displayed.