起落架有限元梁模型建立及其静力学分析

为了获得起落架载荷传递以及评估几何非线性和静不定对起落架载荷传递的影响,同时探索起落架结构有限元梁模型的建模方法,应用HyperMesh和Ansys联合仿真的方法搭建某型具有局部静不定特征的前起落架、主起落架有限元梁模型;使用此模型进行三种载荷工况的静力学计算,获得考虑静不定和几何非线性的起落架接头和截面载荷,以及在单位载荷作用下起落架的航向、侧向和扭转刚度,并与传统方法计算结果进行对比.结果表明:有限元方法和传统方法获得的接头载荷有差异,部分差异超过了±10％,最大差异达到30％;计算前起落架外筒横梁、斜梁截面内力的传统方法及其简化具有合理性,对起落架支柱设计具有指导意义.

Establishing FEA Beam Model of Landing Gear and Application on Statics

In order to obtain load path of landing gear and evaluate load path impact of geometry nonlinear and static indeterminacy, meanwhile to explore method of building FEA beam model of landing gear. The FEA beam models of specific type nose and main landing gear with feature of local static indeterminacy were built by way of HyperMesh and Ansys co-simulation. Static calculation of three load cases was conducted using the FEA model. The boundary load and section load of landing gear with feature of static indeterminacy and geometry nonlinear was obtained, and fore/aft stiffness, lateral stiffness and torsion stiffness of the gear was obtained under one unit load. Comparison with traditional method was conducted. Some conclusion was made: (1) There was difference between boundary load of the two methods. Some difference exceeded ±10% and the biggest difference achieved 30%. (2) The traditional method and simplification of calculating section load of level beam and inclined beam of nose strut was reasonable and had guidance meaning of design nose strut.