垂直发射条件下水下航行体头型对通气空泡流动及压力特性的影响分析  

INVESTIGATION ON THE IMPACT OF UNDERWATER VEHICLE HEAD SHAPES ON THE FLOW AND PRESSURE CHARACTERISTICS OF VENTILATED CAVITY UNDER VERTICAL EMISSION CONDITIONS

作　　者：任泽宇 王小刚[1] 权晓波 程少华 Ren Zeyu;Wang Xiaogang;Quan Xiaobo;Cheng Shaohua(School of Astronautics,Harbin Institute of Technology,Harbin 150001,China;Beijing Institute of Aerospace Systems Engineering,Beijing 100076,China)

机构地区：[1]哈尔滨工业大学航天学院,哈尔滨150001 [2]北京宇航系统工程研究所,北京100076

出　　处：《力学学报》2023年第11期2518-2530,共13页Chinese Journal of Theoretical and Applied Mechanics

基　　金：国家自然科学基金资助项目(U20B2005)。

摘　　要：为了揭示垂直发射条件下水下航行体头型对通气空泡演化过程的力学影响机理,首先基于有限体积法,结合改进型延迟分离涡模型、流体体积多相流模型及重叠网格技术建立了垂直发射条件下通气空泡的数值计算模型.其次,将计算结果与垂直发射实验进行对比,验证了所提出的数值方法对通气云空泡的预测具有较高精度,说明了该方法在通气空泡复杂非定常计算中的适用性.最后,对比研究了相同工况下流线头型和钝头头型航行体通气空泡流动特性和压力特性的差异,从涡量动力学的角度分析了差异产生的原因,结果表明:相比于流线头型航行体,钝头航行体通气空泡气液交界面处速度梯度较小,受到重力和浮力的影响更大,在瑞利-泰勒不稳定性机制的作用下,通气空泡更早发生非线性失稳,空泡失稳区域呈现更为剧烈的浮动行为以及空泡脱落等非定常流动特性;较强的空泡非定常流动特性影响了钝头航行体通气空泡末端的流动分离,从而抑制了空泡末端滞止高压的高幅值特性.This paper aims to explore the impact of underwater vehicle head shapes on the evolution of ventilated cavity under vertical emission conditions.Firstly,based on the finite volume method,the numerical calculation model for ventilated cavitation under the vertical emission condition is established,in which the improved delayed detached eddy simulation,the volume of fluid multiphase flow model and the overlapping mesh technique are adopted.Subsequently,compared with the vertical emission experiments,the validity of the numerical method was confirmed for predicting ventilated cloudy cavity,which demonstrates the applicability of the method in the complex unsteady calculation.Finally,the study compares the flow and pressure characteristics of ventilated cavity of streamline head and blunt head vehicle under the same working conditions,and the reasons for the observed differences are analyzed from the perspective of vortex dynamics.The results indicates that,compared to streamlined-head vehicle,the ventilated cavity of the blunt-headed vehicle experiences a smaller velocity gradient at the gas-liquid interface and is more influenced by gravity and buoyancy,leading to an earlier nonlinear instability under the action of the Rayleigh-Taylor instability mechanism.Additionally,the cavity shows more dramatic unsteady flow characteristics,e.g.floating behavior and cavity shedding,which influence the flow separation at the end of the ventilated cavity of the blunt-headed vehicle,resulting in suppression of high amplitude characteristics of stagnation high pressure.

关 键 词：垂直发射 水下航行体 通气空泡 通气云空泡 空泡脱落 

分 类 号：TJ762[兵器科学与技术—武器系统与运用工程]