Recycling of Krylov Subspaces in the Simulation of Nonlinear Dynamic Systems

ABSTRACT The paper deals with the implementation of a Krylov subspace recycling method into the solution of a nonlinear system of equations that arises during the time integration of the equations of motion of a hydrodynamically supported rotor system. The recycling BiCGStab algorithm is used in order to speed up the calculation. Different methods for generating the necessary subspace are pointed out. Additionally, a new method for the approximate determination of the subspace is presented and discussed in the context of the numerical effort and usability w.r.t. the established methods.