Computation of Single Eigenfrequencies and Eigenfunctions of Plate and Shell Structures Using an H-adaptive FE-method

摘要

The accuracy of the computation of eigenfrequencies and eigenfunctions with FE-methods can be substantially improved with efficient adaptive procedures. For such an adaptive analysis of plate and shell structures a simple a-posteriori error estimator or indicator for the error in the energy norm and L 2-norm of the eigenfunction u h for shell and plate structures is proposed.Both indicators hite shall represent the correct convergence of the estimated error. The estimator for the error in the energy norm is used to enlarge adaptively the dimension of the finite element subspace. On the basis of numerical examples the efficiency and the quality of the improved solution is discussed. In order to validate the quantity of the estimated error Aitken’s extrapolation technique is applied.