空化盘调控下的超空泡航行体入水转平特性研究

Study on Characteristics of Water Entry Leveling of Supercavitating Vehicles under Control of Cavitation Disks

摘要:

本基于 VOF 均相流模型，耦合 SST k-ω 湍流模型、Schnerr-Sauer 空化模型及重叠网格技术，建立了高速入水多相流场与航行体多自由度运动的耦合数值模型，系统研究了空化盘预置偏角对超空泡航行体小角度入水转平特性影响及其调控机理。研究表明：航行体入水转平过程呈现三阶段演化特征——空泡形成阶段，空泡全包裹阶段以及尾拍滑行阶段；数值分析揭示了空化盘预置偏角的调控机制，其产生的法向载荷可达航行体重力的量级，并通过稳定抬头力矩主导姿态调整；增加空化盘预置偏转角可显著提高航行体受到的法向载荷分量以提高其俯仰角速度，有利于实现不同入水深度的定深直航控制，但偏角过大也容易导致航行体弹道失稳。研究结果可为超空泡航行体入水弹道设计与姿态控制提供参考。

Abstract:

In this study，based on the VOF homogeneous flow model，coupled with SST k-ω turbulence model， Schnerr-Sauer cavitation model and overlapping grid technology，a coupled numerical model of high-speed water entry multiphase flow field and multi-degree-of-freedom motion of the vehicle is established. The influence of the preset deflection angle of the cavitation disk on the small-angle water entry characteristics of the supercavitating vehicle and its control mechanism are systematically studied. The research shows that the process of water entry and leveling of the vehicle presents three stages of evolution characteristics cavitation formation stage，cavitation full package stage and tail-slap sliding stage. The numerical analysis reveals the control mechanism of the preset deflection angle of the cavitation disk. The normal load generated by the cavitation disk can reach the magnitude of the sailing body weight force，and the attitude adjustment is dominated by the stable head-up moment. Increasing the preset deflection angle of the cavitation disk can significantly increase the normal load component of the vehicle to increase its pitch angular velocity，which is conducive to the realization of fixed depth direct navigation control at different water entry depths. However，too large deflection angle can also easily lead to ballistic instability of the vehicle. The research results can provide reference for the water entry trajectory design and attitude control of supercavitating vehicles.