Influence of ventilation parameters on water entry cavitation of disk cavitation vehicle

In order to explore the impact of ventilation parameters on the characteristics of water entry cavitation, the VOF multi-phase flow model, the realizable k-ε turbulence model and the Singhal cavitation model are used to establish the high-speed water entry flow field simulation method. The comparison with the experimental results from open literature verifies the feasibility of the simulation method. The influence of ventilation parameters on the ventilation super-foam shape is studied. The results show that the ventilation from behind a cavitation device is conducive to the generation and development of a water entry super-foam and can promote the gas flow in the foam, extending the time for water entry foam closure and increasing its size. When the cavitation is not closed at the beginning of water entry, ventilation or not has little effect on the shape of the foam, whose maximum diameter difference is within 0.015D. In the continuous water entry process, the size of the foam increases with the increasing ventilation, which increases the foam size significantly. When the ventilation rate is 4.74, the length of the foam increases by 0.32D; its diameter increases by 25%. The ventilation from behind the cavitation device can delay water entry foam closure. The greater the amount of ventilation, the longer the time for foam closure. When the ventilation rate is 2.37, the closure time is 3.2 ms; when the ventilation rate is 4.74, the closure time is 4 ms, indicating that when the amount of ventilation doubles, the foam closure delays by 25%.