超单元在民用飞机全机内力计算中的应用研究

Application of super element in internal load analysis of civil aircraft

作为飞机结构强度分析的有效手段,飞机全机有限元模型内力计算结果直接影响强度分析结论。超单元方法作为求解大型有限元问题的有效手段,在飞机全机内力计算中具有较好的适用性。基于超单元方法的基本理论以及NASTRAN软件,给出超单元方法在民用飞机全机内力计算的使用方法和步骤。以某型民用飞机全机模型内力计算为例,进行了超单元方法计算与全模型方法计算,并对比两种方法得到的节点位移以及单元内力。结果表明,超单元方法计算误差较小,对结果的影响可忽略不计,可用于飞机全机有限元模型内力计算。

As an effective method of aircraft strength analysis,the internal load calculation of the aircraft finite element model directly affects the strength conclusion.As an effective method to solve large scale finite element problems,super element method has good applicability in the calculation of internal load analysis of civil aircraft.Based on the theory of super element and NASTRAN software,the method and step of super element in internal load analysis are given.Taking the internal force calculation of a civil aircraft model as an example,the super element method and traditional analysis method are carried out,and the node displacement and element internal force obtained by two methods are compared.The results indicate that the calculation error of super element method is small,and the influence on the results can be ignored,which means the super element method can be used in the internal load analysis of civil aircraft.