Advanced Mode Analysis for Crash Simulation Results

Potential scatter of simulation results caused for exampleby buckling, is still a challenging issue for the predictability. Principle component analysis (PCA) is a well-known mathematical method for data analysis. In order to characterize scatter PCA analysis was applied to the simulation results from a number of runs using all node positions at all time steps. For industrials relevant problems the size of the data base is larger than 100 GBytes (even, if compressed by FEMzip1[7]) . As a result the major components dominating the differences between the simulation results are available. Since PCA is a mathematically based method, the selected modes do not separate different physical effects like buckling at different parts of the model. PCA rather tries to maximize the variations by combining several physical effects into one mode. Difference PCA(DPCA) applies PCA analysis to the results for each part and time step. By analysis of the related covariance matrices, the local dimension of the scatter subspace can be identified and correlation between the scatter at different places can be analyzed. Using DPCA, different origins of scatter can be identified and physically meaningful components can be determined. The paper introduces the approach and shows results for an industrial model.