应急断离剪切销的双剪切破坏过程仿真研究

Simulation study on double shear failure process of emergency breaking shear pin

民用飞机吊挂应急断离剪切销需要在紧急情况下断开并使得吊挂或者发动机脱离机翼,避免飞机在紧急着陆时,吊挂结构因受到地面反弹而损坏机翼油箱,导致油箱漏油起火引发火灾。因此应急断离剪切销对于飞机紧急着陆状态下,飞机安全着陆起到了非常重要的作用。本文以不锈钢材料的应急断离剪切销为研究对象,通过试验方法对不锈钢材料的试件进行力学性能测试,根据测试结果建立了应急断离剪切销的弹塑性本构模型,依据本构模型开展了2种不同径厚比下的应急断离剪切销双剪仿真分析。分析结果表明,在双剪工况下,随着施加在剪切销上的载荷增加,应急断离剪切销上剪切应力在两侧不断增加;剪切销的内径越大,其破坏瞬间的剪切强度越大,且破坏位移越大。

The emergency breakaway shear pin needs to be disconnected in case of emergency and make the hanging or engine separate from the wing,in order to prevent the hanging structure from damaging the wing oil tank due to the rebound of the ground during the emergency landing.In this paper,stainless steel material shear pin is taken as the research object,and the mechanical properties of the material are tested by the test method.According to the test results,the elastic-plastic constitutive model of the shear pin is established,and the double shear simulation analysis of the breakaway pin under two different diameter thickness ratios is carried out according to the constitutive model.The results show that under the double shear condition,with the increase of applied load,the shear stress on both sides of the pin increases continuously;the larger the inner diameter is,the greater the shear strength at the moment of failure is,the greater the failure displacement is.