水下非流线型航行体减阻的数值模拟与比较

NUMERICAL SIMULATION AND COMPARISON ON DRAG REDUCTION OF NON-STREAMLINE SUBMERGED BODY

针对某水下非流线型航行体的试验模型,采用混合均质流理论、Realizableκ?ε湍流模型进行了自然状态和通气产生超空泡状态下阻力的数值模拟,通过对流线型航行体的数值模拟和经验公式的比较验证了采用方法的适用性,得到了自然和通气状态下非流线型水下航行体的阻力变化规律。计算结果表明,自然状态下非流线型航行体的阻力比流线型的大大增加,压差阻力成为主要成份,但通气形成超空泡后可以大大降低航行体的阻力,在小空化数下摩擦阻力可以忽略。

Taking a non-streamline submerged body as a model, its drags under the natural condition and artificial ventilated condition are numerically simulated using mixed homogeneous flow theory and realizable κ-ε turbulence model. Numerical simulation of a streamline body＇s drag with the above method is compared with approximate formula calculation and the applicability of numerical method is verified. The regulations of the drags of non-streamline submerged body under the natural condition and artificial ventilated condition are found. The result shows that the drag of non-streamline submerged body under natural condition is greatly increased compared with that of streamline body, and the pressure drag is the main component. However, after artificial ventilation and the supercavity is formed, the drag is greatly decreased. The viscous drag can be ignored when the cavity number is small enough.