增压载荷下机身蒙皮细节应力分布计算方法研究

The Detailed Stress Distribution Analysis of Skin under the Pressure Load

为了获取增压载荷作用下机身蒙皮疲劳分析部位较为精确的应力分布,结合某机型机身等直段结构,采用NASTRAN有限元分析软件,在总体有限元模型基础上,对局部区域进行网格细化,建立了细节有限元模型,给出了窗周区域载荷施加的简化处理方法,获得了机身典型壁板区域以及窗周区域蒙皮应力分布规律,并将典型壁板区域某截面细节有限元模型分析结果与试验测试结果进行了比较,结果表明,两者数据吻合较好。最后,提出一种用于疲劳强度分析的蒙皮细节应力分布获取方法,采用该方法能够类比获取同一机型同类结构蒙皮细节应力分布。

In order to obtain the accurate stress distribution of the fuselage skin under the pressure load, NASTRAN software was used to refine the local mesh quality of the barrel structure, in this process, the method of load simplification of window zone was raised. The rules of stress distribution in typical panel and window zone were obtained by the FEM analysis, then the analysis result was compared with the test result. The contrastive analysis showed that both data were almost identical. At the last, the obtaining method of the detailed stress distribution for fatigue assessment was put forward, the stress distribution of the same kind of structures could be calculated using this method.