Multiparametric shell eigenvalue problems

Harri Hakula; Mikael Laaksonen

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arXiv · 1803.03854

Multiparametric shell eigenvalue problems

Harri Hakula·Mikael Laaksonen

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Abstract

The eigenproblem for thin shells of revolution under uncertainty in material parameters is discussed. Here the focus is on the smallest eigenpairs. Shells of revolution have natural eigenclusters due to symmetries, moreover, the eigenpairs depend on a deterministic parameter, the dimensionless thickness. The stochastic subspace iteration algorithms presented here are capable of resolving the smallest eigenclusters. In the case of random material parameters, it is possible that the eigenmodes cross in the stochastic parameter space. This interesting phenomenon is demonstrated via numerical experiments. Finally, the effect of the chosen material model on the asymptotics in relation to the deterministic parameter is shown to be negligible.

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Harri Hakula, Mikael Laaksonen. 2018-03-10. Multiparametric shell eigenvalue problems. https://arxiv.org/abs/1803.03854

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