机翼机身对接接头非线性有限元分析

Nonlinear Finite Element Analysis of Wing-Fuselage Connection Joint

接头是飞机结构中常见的结构连接形式,也往往是强度破坏或疲劳破坏的部位。有时为了更大的挖掘接头结构的承载能力,甚至还要考虑结构局部进入塑性区应力分布,属于材料非线性和力边界非线性的耦合问题。试图通过直接求解偏微分方程得到接头接触问题的解析解是很难的,甚至可以说是不可能的。基于非线性有限元分析方法,借助大型通用有限元软件MARC的弹塑性接触分析模块,通过不断细化网格的方法来对机翼机身对接接头进行非线性耦合分析。建立了对接接头的弹塑性接触有限元模型,给出了接头的应力分布以及屈服状况。数值模拟结果与实际情况相符,数值模拟结果为机身机翼对接接头的设计提供了重要的数据。

The aircraft structure joint is a common form of structural connection often damaged due to intensity or fatigue. Sometimes in order to use the carrying capacity of the joint structure more sufficiently, even the stress distribution and the coupling issues of material nonlinearity and border nonlinearity should be considered. Solveing partial differential equations by directly contacting with the joint analytical solution is very difficult, if not impossible. Based on the nonlinear finite element analysis method, the large - scale finite element software MARC elastoplastic contact analysis module is proposed to do the nonlinear coupling analysis for wing - fuselage connection joint through continuous refinement grid approach. The elastoplastic contact finite element model of wing - fuselage connection joint is established, and the stress distribution and joint yield status are provided. It is shown that the numerical results accord with the actual situation, and the numerical results can provide important data for the wing - fuselage connection joint.