AD.2007-11.1.2 Advanced Analysis Engine Enhancements
The advanced analysis engine has been completely reformatted with new routines to provide even faster methods to build and solve the stiffness matrix.
Arnoldi/Lanczos Eigen Method
In addition to the standard supbspace iteration method for eigen solution, the Advanced Math Solver can use the Arnoldi/Lanczos method. For large scale eigen value problems, the Arnoldi method is very efficient.
Load Dependant Ritz Vectors
Ritz vector analysis can be used for dynamically loaded structures to more efficiently evaluate the relevant modes. It can require significantly less computational effort to evaluate a large structure when compared to natural free-vibration methods.
Autoshfiting of Eigen Vectors
For subspace iteration and the Arnoldi/Lanczos methods, an autoshift option can be used to reduce memory demand for large structures.
Refer to G.17.3.1 Solution of the Eigenproblem for details.