Dynamic Analysis for Sleeve Structure Using Non-Linear Finite Element Method

Sleeve structure is in common use for aerospace like launch vehicle and the analysis for sleeve structure is difficult for mechanics modeling. The sleeve structure is an incompletely rigid joint and the contact stiffness is non-linear and it must be taken into account for static or dynamic analysis. Nonlinear finite element method is one of numerical method to analyze the sleeve structure. In this paper, the gap element of MSN/NASTRAN is used to solve the contact problem. The mechanical characteristic of gap element is analyzed. A method for defining the close stiffness of gap element is proposed and the sleeve structure's dynamic characteristic is calculated by the software. Compared with the experimental results, the method is proved to be valid and reasonable.