潜射导弹出水过程空化流数值计算

Numerical investigation of water-exit cavitation flow of submarine-launched missile

运用Zwart-Gerber-Belamri空化模型,采用动网格和复合网格技术,提出复杂外形潜射导弹出水过程中空化流数值计算方法。对头肩部、舵面及突起物的空化生成、演化及影响因素进行分析。仿真结果表明：出水过程初期空化数降低使附体空泡迅速扩大,随后对空泡脱落与振荡的影响将更为显著;肩部以15 m/s的速度出水时产生空化并随速度上升而迅速增长,5°~10°攻角时肩空化非对称性显现;舵面空化受出水速度影响较小,攻角小于等于5°时空化面积小于全舵面积的10%,但攻角大于5°后空化面积迅速增长至50%以上;减小突起物尺寸有利于避免空化产生,突起物空化受攻角影响较小,但在高速下可诱导临近弹体产生空化。

Based on Zwart-Gerber-Belamri cavitation model,a numerical calculation method of cavity flow of water-exit missile with complex configuration was proposed,in which the technology of dynamic mesh and composite mesh was used. Cavitation formation,evolvement and influence of shoulder,rudder and protuberance of water-exit missile were analyzed. The simulation results acclaim that in the beginning of waterexit course,body-attached bubble quickly grows due to reduction of cavitation number. After that,the effect of bubble break-off and oscillation becomes more obvious. The cavitation of shoulder firstly appears at the water-exit speed of 15 m / s. And it grows quickly with water-exit speed. The dissymmetry of shoulder cavitation becomes obvious in the attack angle of 5° ~ 10°. The cavitation of rudder is hardly influenced by water-exit speed. The proportion of cavitation area of rudder is less than 10% when the attack angle is less than 5°,and rapidly increases to 50% when the attack angle beyond 5°. Reduction of protuberance size is beneficial to cavitation avoidance. The influence of the attack angle on protuberance cavitation is unapparent. Protuberance can induce the cavitation on nearby missile body at high speed.