超空泡航行体楔形舵片流体动力学特性数值模拟

Numerical simulation on hydrodynamic characteristics of rudders of supercavitating vehicle on maneuvering condition

舵片是保证超空泡航行体运动稳定性和控制航行弹道的重要部分。文章基于均质平衡流模型和SST(Shear Stress Transport)湍流模型,计算了单独舵片的流体动力特性,并与试验数据进行了对比,结果符合较好,验证了计算模型的有效性。基于此方法,计算了单独舵片发生空化后在不同操舵状态下的非定常流体动力变化。结果表明,在攻角相同时,操舵状态下舵片的非定常升力系数和定常结果差别不大,而非定常阻力系数大于定常结果,并且操舵速度越快,阻力系数越大。另外计算了舵片发生空化后的流体动力系数,结果显示在攻角相同时,舵片的阻力系数和升力系数均小于其在全湿状态下的结果;在空化状态下,舵片升力系数的斜率小于全湿状态,并且舵片升力系数的斜率是变化的,存在某临界攻角,攻角大于此临界值时,升力系数的斜率减小,而此临界攻角恰好为舵片的吸力面刚刚出现空化时的攻角;操舵状态下舵片的阻力系数和升力系数的变化规律与定常结果一致,但是数值偏小。

The control technology of supercavitating underwater vehicle is one of the most important methods for optimizing the trajectory of supercavitating underwater vehicles, and the critical point of which is the rudder control. Based on the homogeneous model and SST turbulent model, the lift coefficient of a single rudder was obtained, and the data fit well with the experiment result. Using the same method, the lift and drag characteristics of the single rudder are simulated while the attack angle is changed. The results show that the lift coefficient of the transient result is bigger than that of the steady result. Then the lift and drag characteristics of the single rudder are simulated when cavitation occurs. The results show that there is a critical attack angle at which the slope of the lift coefficient curve decreases. The lift and drag coefficient decreases when cavitation occurs.