A numerical method for eigensolution of locally modified systems based on the inverse power method

Rapid reanalysis of eigensolutions after modification is a problem of considerable practical importance. Several methods have been developed for computing eigenvalues by using modified parts. This paper proposes just such a method based on inverse power method, using the DOF of only the modified part. This approach enables exact solutions for eigenvalues to be found quickly, regardless of the magnitude of the modification, using the degree of the condensed modified part. The advantages of the proposed method are examined comparing the solutions of inverse power method by several numerical examples. This approach will be useful for a modified system with large degrees of freedom and small modification part.