STUDY ON THE UNSTEADY VERTICAL CAVITY OF THE EXIT-WATER CAVITOR

The unsteady vertical cavity produced by the underwater cavitator moving rapidly towards the water surface is investigated theoretically. The mathematical model of the unsteady vertical cavity under water is presented; the formula of the vertical cavity length influenced by the gravity and water surface is derived, and the life span of cavity shedding from exit-water cavitator is also obtained from the formula. For the underwater body with cavitator, the acting position in the body of the high-pressure produced by the collapsed cavity is also calculated by the formula; moreover, the condition and criterion of keeping the underwater body from collapse high-pressure is presented.