多重扰动下通气超空泡稳定性模拟研究

Numerical Simulation of the Stability of Ventilated Supercavitation under Various Types of Disturbances

根据Logvinovich独立膨胀原理和质量守恒方程建立非定常通气超空泡数学模型,并基于此模型,分别考虑了通气扰动、速度扰动、空化器转动扰动及其组合多重扰动情况,对超空泡形态进行了数值模拟,进而对超空泡的稳定性进行了分析。研究表明:速度扰动对通气超空泡形态稳定性起主导性作用,其扰动带来的空泡振荡特性也最强烈;空化器转动扰动能小幅度影响超空泡形态,并决定空泡恢复稳定后的最终长度;通气扰动作用相对微弱,三者扰动同时存在时,其作用几乎可以忽略。

A mathematical model of unsteady ventilated supercavitation is established based on the princi- ple of Logvinovich of the cavity sections expansion and mass conservation equation. The mathematical model is used to simulate the shape stability of ventilated supercavitation under the disturbances of air- supply rate, cavitator, velocity and some combination perturbation, respectively, and then the stability of ventilated supercavitation is analyzed. The results indicate that the disturbance of velocity plays a crucial role in the shape stability of ventilated supercavitation, and the oscillation of cavity is strong, the disturb- ance of cavitator can influence the shape stability of ventilated supercavitation with low-amplitude and de- termine the last length of cavity, the disturbance of air-supply rate is small compared with the others and can be ignored when they exist.