Application of the impedance coupling method and the equivalent rotor model in rotordynamics
Several coupling algorithms are well established for combining the characteristics of substructures. These methodologies provide an efficient synthesis of total structural dynamics from the finite element results or experimentally measured data of its substructures. This paper presents the application of the impedance coupling method and the equivalent rotor model for including the support dynamics on the interaction with the rotor. Firstly, impedance coupling technique is applied to the pump system, which is based on the FRFs of each substructure and constraint conditions in the connection coordinates. An alternative approach, the equivalent rotor model, uses springmass models which are equivalent to the FRFs of the support structure, i.e. the extracted springmass models are directly incorporated into the finite element rotor model. To verify the two suggested analytical procedures, the results of each model are compared to results from a full finite element model of the pump system.
impedance coupling method frf dynamic stiffness matrix finite element method