Experimental Study on Morphological Characteristics of Ventilated Supercavity of Double Disc Cavitator Projectile

双圆盘空化器射弹通气超空泡形态特性实验研究

School of Marine Science and Technology, Northwestern Polytechnical University, Xi’an 710072, China

Received: 2 March 2018

Abstract

Based on the principle of independence of cavity sections expansion, a double disc cavitator for underwater projectiles is proposed in this paper.The high-speed water tunnel experiment is carried out to study the generation and morphological characteristics of the ventilated supercavity which generated by this series of double disc cavitator.The experiment observed the ventilated supercavity morphology under the different cone angles by changing the ventilation flow coefficient.The experimental results show that there are two kinds of cavitation states:the front disc preferential cavitation and the rear disc preferential cavitation. The transition between these two states occur at a cone angle about 55°.The value of the critical ventilation flow coefficient when generating stable ventilation supercavity has a positive correlation with the cone angle.The front disc and the rear disc of the cavitator have mutual inhibitory effect on the production of ventilated supercavities.And the morphological characteristics of ventilated supercavity do not increase with the increasing of ventilation flow coefficient, but there is an upper limit value of ventilation flow coefficient.

摘要

基于空泡截面独立扩张原理，提出了一种应用于水下射弹的双圆盘空化器。并在高速循环水洞中对此系列双圆盘空化器的空泡生成特性和形态特性进行实验研究。实验通过改变通气流量系数，观察了不同锥顶角下的通气超空泡形态。实验表明，此系列双圆盘空化器诱导生成的通气超空泡存在前盘优先和后盘优先2种空化状态，二者的过渡发生在锥顶角55°附近；生成稳定通气超空泡的临界通气流量系数值与锥顶角呈正相关趋势，前盘和后盘对空泡生成具有相互抑制作用；且通气超空泡的形态特征量不随通气流量系数增加而持续增加，而是存在一个通气流量系数上限值。