回转体自然空化阻力特性数值仿真

摘要

In order to research the drag coefficient of underwater vehicles by the local cavity that results from natural cavitation, based on k-ε model and mixture model, the natural cavitating characteristic and drag coefficient on axisymmetric body were numerically simulated at different cavitation number. Result shows that the local cavity increases the total drag coefficient; the initial cavity occurs on the vehicle surface at a critical cavitation number; the pressure drag coefficient is up to maximum at another critical cavitation number, and it almost the same as the cavitation number at maximal total drag coefficient. The conclusion and numerical computational methods are of value to research and computation on actual projects.%针对水下航行器壁面出现自然空化现象影响航行速度问题,为了研究由自然空化引起的局部空泡对水下航行器阻力系数的影响.根据标准k-ε双方程,采用混合模型对不同空化数下回转体自然空泡特性以及阻力系数在Fluent6.3软件上进行了数值仿真.结果表明,局部空化的出现增大了总阻力系数.由于存在一临界空化数,使得航行器表面出现自然空化,存在另一临界空化数,使得压差阻力系数达到最大,并且此空化数与总阻力系数达到最大时的空化数相差不大.求解结果证明,方法的正确性和有效性.