气动加载与振动激励耦合试验方法研究

飞机结构在飞行过程中同时承受气动载荷和振动载荷的联合作用,这两种载荷的耦合加载试验对于飞机结构成为一项重要的研究内容,所以有必要对此类试验的可行性及其耦合加载方式进行研究。此次试验以气囊加载静载/常规疲劳载荷状态下试件的振动响应测试为目的,设计符合试验要求的试件和整套试验装置。得到了气囊5种不同加载情况下试件振动响应变化情况,并对此试验结果进行了理论分析,得出以下结论:a)气囊模拟静载/常规疲劳载荷加载不会大幅改变结构本身振动特性,此耦合试验方法所模拟环境比较接近飞机结构真实载荷环境;b)加载气囊的个数、部位及加载力的不同对试件结构的振动响应有一定影响,应增加气囊蓄能器或在试验前进行分析以选择合理的加载点。

On The Experimental Method of Aerodynamic Loading and Vibration Excitation Coupling

During the flight, aircraft structure withstands simultaneously the combined action of aerodynamic load and vibration load. For aircraft structure, the coupling loading experiment of these two loads is an important study content. So it is necessary to conduct a study of coupling loading means and the feasibility of experiment. The aim of this experiment is the vibration response measurement of specimen subjected to airbag loaded static load/conventional fatigue loads. Based on which, the specimens meet the experimental requirement and set of experimental device were designed. Specimen's vibration responses under five different airbag loadings were obtained. Then the experimental results were theoretically analyzed. Conclusions are: 1) airbag loaded static load/conventional fatigue loading will not significantly change the vibration characteristics of aircraft structure itself, the simulated environment by this coupling loading is closer to real environment of aircraft structure; 2)The airbag number, their location and loading amplitudes do affect specimen's vibration response. So, the number of airbag accumulator should be increased, or reasonable loading positions should be selected based on the analysis before experiment.