Research On Spacecraft Section Vibration Environment Prediction Methods

Mechanical environment is an important part of the aerospace design. The complex spacecraft section vibration environment prediction methods are explored through the finite element analysis(FEA) and statistical energy analysis(SEA). The result is of important engineering value. The main works in this thesis as follow:Firstly, based on the FEM software MSC.Patran and Nastran, a structure is calculated by FEA. The FE model is established and simplified. Frequency response analysis is computed by using acceleration excitation. The model forecast response is evaluated by contrasting the transfer function. Based on this, FE model is modified and accurate reliable model is provided for future research.Secondly, SEA is used to calculate the structural response at higher frequencies. Based on the commercial software Auto SEA2, its SEA model is established and every subsystem's damping loss factor, coupling loss factor and modal density are discussed and determined. The study shows that SEA can supplement the defects of FEA in the high frequency vibration structural response.The complex structure is calculated to achieve the full frequency domain vibration environment prediction by FEA and SEA. It is of great reference value for future development of the complex structure's vibration environment prediction technology.