This algorithm allows obtaining eigenvalues if information about them. It is an excellent tool for those who have some experience in structure dynamic analysis and when dynamic behavior of a designed structure is known.
The basis reduction method involves solving the equation system of eigenvalue problems Kφ - λBφ = 0. This is the Ritz method and since it is not an iterative approach, precision is not verified. The tol parameter provided in the Modal Analysis Parameters dialog is ignored.
In this method it is required to define the master degrees of freedom (MDOF) which enable acquiring a reduced model. The method allows unneeded degrees of freedom to be excluded from the reduced model, leading to a significantly smaller system of equations.
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