Porpoising instability is a tough nut bewildering ocean academia for years. This study provides the first experiment found that the cavity formed by artificial ventilation can significantly inhibit the inherent porpoising instability of planing vessel under high/ultra-high forward speeds. Restricted by the occurrence of porpoising instability, a Froude number (volume of displacement based) upper limit of 5.91 is reached at the current conventional ship model calm water towing experiment. However, this instability phenomenon disappears when a cavity is formed at the bottom of ventilation ship model within all experimentally Froude number range (5.91−6.82). The inhibition effect can be tracked from the timing sequences value of trim. The decrease in trim value, to the degree below the threshold of porpoising instability, is responsible for the disappearance of this longitudinal instability. The enhancement in longitudinal stability is believed to be directly related to the increase in volume of displacement led by the cavity, which greatly reinforces the impact of hydrostatic lift in the vertical force balance. The strengthening of hydrostatic lift attenuates the influence of dynamic instability caused by fluid dynamic pressure. Therefore, if an external disturbance is given to the vessel, the disturbing moment around the center of rotation is weakened, which prevents the strong periodic alternation between inertial and restorative forces.

海豚不稳定是困扰海洋学术界多年的难题。这项研究提供了第一个实验，发现在高/超高前进速度下，通过人工通风形成的空腔可以显着抑制滑行船固有的成穴不稳定性。受制于海豚失稳的限制，在当前常规船舶模型平静水拖曳实验中，弗洛德数（基于位移的体积）上限为5.91。但是，当在所有实验弗劳德数范围（5.91-6.82）内在通风船模型的底部形成空腔时，这种不稳定性现象就会消失。可以从调整的时序值中跟踪抑制效果。修剪值的降低，直至低于海豚不稳定性阈值的程度，是造成这种纵向不稳定性的原因。相信纵向稳定性的增强直接与空腔引起的位移量的增加有关，这大大增强了静力升力在垂直力平衡中的影响。静液压升力的增强减弱了流体动压力引起的动态不稳定性的影响。因此，如果对船舶施加外部干扰，则绕旋转中心的干扰力矩会减弱，从而防止了惯性力和恢复力之间的强烈周期性交替。这大大增强了静力升力在垂直力平衡中的影响。静液压升力的增强减弱了流体动压力引起的动态不稳定性的影响。因此，如果对船舶施加外部干扰，则绕旋转中心的干扰力矩会减弱，从而防止了惯性力和恢复力之间的强烈周期性交替。这大大增强了静力升力在垂直力平衡中的影响。静液压升力的增强减弱了流体动压力引起的动态不稳定性的影响。因此，如果对船舶施加外部干扰，则绕旋转中心的干扰力矩会减弱，从而防止了惯性力和恢复力之间的强烈周期性交替。