水下航行体通气超空泡非对称性研究

ON ASYMMETRY OF VENTILATED SUPERCAVITY OF UNDERWATER VEHICLE

超空化水下高速航行体为了满足运动平衡性和稳定性要求,需要采用非对称超空泡流动模式。为了探索满足要求的非对称超空泡流型,在水洞中开展了水下航行体通气超空泡非对称性实验研究。采用通气的方法在较低水速(V=7～12m/s)下生成人工超空泡,通过分析和测量不同弗劳德数、模型攻角、空化器攻角与舵角等实验条件下的超空泡图像,获得了航行体超空泡非对称性与影响因素之间的定量和定性关系。研究表明,当组合参数F_r^2(1+σ)>50时,重力引起的超空泡变形量小于5‰;由模型攻角、空化器攻角和舵角产生的非对称超空泡流型可以满足超空化水下航行体的平衡性要求。

For all its attracktiveness due to a low hydrodynamic drag,the motion of a supercavitating vehicle in a cavity is a more complicated and paradoxical process than that of space craft.Moving in a vaper-or gas- filled,the cavitating vehicle loses buoyancy——the main advantage of motion in water,and thus need dynamic mean8 to maintan its weight in cavity.To keep the balance and stability of the motion,supercavitating underwater vehicle need asymmetrical supercavitating flow patterns.In order to explore the asymmetrical supercavitating flow patterns,a series of experiments were conducted to investigate asymmetry of ventilated supercavity's configuration.Supercavitation is initiated by ventilating at moderate flow speed.By analyzing and measuring the photos of supercavity under conditions of various Froude number,attack angle of model and cavitator,the relations between supercavity asymmetry and the factors those arose it were found qualitatively and quantitatively.The result indicated that when compound parameterFr2(1+σ)is greater than 50,the asymmetrical deformation caused by gravity is less than 5‰.The asymmetricM supercavitating flow pattern can satisfy the requirement of supercavitating motion of underwater vehicle.