基于CFD/CSD耦合的高速射弹尾拍载荷特性研究  

Study on tail-slap load characteristics of high-speed projectile based on CFD/CSD coupling

作　　者：许云涛[1,2] 檀大林 杨超[1] XU Yuntao;TAN Dalin;YANG Chao(School of Aeronautic Science and Engineering,Beihang University,Beijing 100191,China;Beijing Institute of Mechanical and Electrical Engineering,Beijing 100074,China)

机构地区：[1]北京航空航天大学航空科学与工程学院,北京100191 [2]北京机电工程研究所,北京100074

出　　处：《北京航空航天大学学报》2023年第9期2539-2546,共8页Journal of Beijing University of Aeronautics and Astronautics

摘　　要：为提高射弹尾拍载荷的预测精度,建立了一套基于计算流体动力学(CFD)/计算结构动力学(CSD)双向耦合分析的计算方法和程序。射弹流体计算主控方程采用耦合SSTk-ω湍流模型和Schnerr-Sauer空化模型的Navier-Stokes方程,射弹结构计算采用基于模态叠加法简化的结构动力学方程,流固耦合界面插值采用径向基函数法,网格变形采用弹簧网格法。分别对泡型计算方法和流固耦合方法进行验证,在此基础上,计算对比1 000 m/s速度下射弹刚体和弹性体的尾拍泡型、结构变形和尾拍流体载荷特性差异。计算表明:弹性体尾拍过程,射弹泡型会产生弹身“二次拍击”、“局部沾湿”和沾湿面积增大等特殊现象,结构变形由弹性一弯模态主导,较大的变形引起流体载荷增大27%~105%,尾拍姿态角增大13%,尾拍频率增加20%,流固耦合效应对尾拍泡型、尾拍载荷和尾拍弹道均产生了较强的影响。A calculating approach based on the two-way analysis of computational fluid dynamics(CFD)/computational structure dynamics(CSD)coupling is devised to increase the predictability of the projectile’s tail-slap load.The main governing equation of fluid calculation adopts the Navier-Stokes equation with SST k-ωturbulent flow model and Schnerr-Sauer cavitation model,structural calculations use simplified structural dynamic equations based on the modal superposition method,interpolation of fluid-structural coupling interface using radial basis function method,mesh deformation using spring stretching method.Both the fluid-structural coupling approach and the cavity shape computation method were independently verified.Further,the differences in cavity shape,structural deformation,and characteristics of tail-slap loads between the rigid body and the elastic body of the projectile at a speed of 1000 m/s were calculated and compared.Simulation results show that during the tail-slapping process of the elastic body,the cavity shape of the projectile will produce special phenomena such as‘secondary slap’,‘partial wetting’and a wetting area increased.Structural deformation is dominated by the first-bending mode.The larger deformation causes the dynamic load to increase by 27%~105%,the amplitude of the pitch angle to increase by 13%,and the tail-slapping frequency to increase by 20%.The fluid-structural coupling effect has a strong influence on the cavity shape,loads,and ballistic of tail-slapping.

关 键 词：射弹 CFD/CSD耦合 尾拍 载荷 刚体 弹性体 

分 类 号：TJ630[兵器科学与技术—武器系统与运用工程]