在自行研制的实验装置上,进行了完全超空泡出水过程的实验。用高速摄影机对出水过程进行了拍摄,发现当水下航行体接近水面时,会发生超空泡的崩溃;然后,水下航行体继续产生超空泡,等到出水进入大气之后,再次发生空泡的溃灭。有时超空泡在水下还来不及崩溃,就被航行体带出水面,只发生在大气中的崩溃。在实验研究的基础上,建立了超空泡在运动过程中崩溃次数的理论模型。此外,还将测得的超空泡形状,与已有的半经验公式进行了对比。
Supercavitation flow means that an underwater body moves in a vapour or gas cavity instead of water.This paper presents an experimental research on water exit of a fully developed supercavity by high-speed photography.It is found that,when the underwater supercavitating vehicle approaches free surface, the supercavity collapses;after that,the vehicle generates a new supercavity which collapses again in air after the vehicle brings it out of the water surface.Sometimes,the supercavity has no time to collapse in water but is carried by the vehicle into open air,where the supercavity collapses.A theoretical model is given to es-timate the collapsing time of a supercavity.Besides,through comparing the measured cavity shape parame-ters with Logvinovich’s and Savchenko’s semi-empirical formulas,both agreement and disagreement are found.