跨声速运动对射弹阻力及空化特性的影响

为研究在跨声速运动过程中超空泡射弹的流体动力特性和流场的空化情况，基于流体体积分数多相流模型、Schnerr-Sauer 空化模型、Realizable k-ε湍流模型、Tait液体状态方程和运动框架模型构建了可压缩超空化流场的数值模型，通过与文献\11\]试验结果进行对比，完成模型验证，采用数值方法模拟在马赫数为0.202~1.281速度范围内射弹的外流场。研究结果显示：跨声速运动过程中超空泡射弹的阻力系数与流场驻点的密度峰值有关，随速度的升高而显著增大；激波对弹体附近超空泡的形态和尺度有显著的影响，亚声速工况下超空泡尺寸与理论值接近并且受速度的影响很小，超声速工况下超空泡的尺寸随速度的增加而大幅度减小。研究结果对超空泡射弹的外形设计和弹道预报有参考价值。

Influence of Transonic motion on Resistance and Cavitation Characteristics of Projectiles

In order to research the resistance characteristics and flow cavitation of supercavitation projectiles during transonic motion, a numerical model of a compressible and supercaitation flow field is established based on VOF multiphase model, Schnerr-Sauer cavitation model, realizable k-ε turbulence model, Tait liquid state equation and moving frame model.The proposed model is validated by comparing the numerical results with those in Ref.\11\], and the external flow field of supercavitation projectile flying at Mach number between 0.202 and 1.281 is simulated. The simulated results show that, during transonic motion , the resistance coefficient of projectile is related to the peak value of density at the stationary point of flow field and increases with the increase in flying speed; and the shockwaves have significant influence on the shapes and dimensions of supercavities near projectile. Under subsonic condition, the flying speed of projectile has no significant influence on the dimensions of supercavities, and the shapes of supercavities coincide with theoretical results; under supersonic condition, the dimensions of supercavities decrease sharply with the increase in flying speed.