局部流动分离诱导结构振动问题的数值模拟

基于非结构网格技术和SST-DES模型,采用流体与结构紧耦合策略,对飞机机身突出物（如雷达罩）下游的蒙皮振动过程进行了数值模拟计算。在求解NS方程过程中,使用有限体积法,结合有限元法求解结构运动方程。在时间域内模拟了不同结构参数和飞机不同迎角下的飞机蒙皮的结构响应,建立了亚音速条件下壁面流固耦合分析方法。计算结果表明：机身突出物诱导出的分离涡的确可以激发下游壁面的振动,其壁面振动的幅度与结构本身参数密切相关,振动主要为发生在壁面的法向上,随着迎角增加,壁面的振动减弱。通过基本原理和算例可以看出,方法可以预测不同条件下壁面的动态响应过程,适用范围宽,可以用于壁面结构的设计。

Numerical Simulation of Vibration Induced by Local Flow Separation

Based on the unstructured grid technique and SST-DES model,the skin vibration process of the downstream bulge of the fuselage(eg,antenna cover)is numerically simulated by adopting the tight coupling strategy in the fluid and structure coupling case.In solving the NS equations,we use the finite volume method in combination with the finite element method to solve the structural motion equation.We simulate different parameters of skin structures and aircraft structural response under different angles of attack in time domain,and establish a FSI analysis method of shell under the subsonic condition.The results show that:the shed vortex induced by separation can indeed excite the vibration of the downstream wall,and the vibrating amplitude of the wall is closely related to its structural parameters.The vibration mainly occurs in the normal direction of the wall.By the basic principle and calculation cases,we can conclude that this method can be used to predict the dynamic response of the wall under different conditions,has a wide application,and can be used to design the structure of the wall.