FRF of a coupled geared system using the frequency based substructuring and condensation methods

Power transmission systems are complex systems and their dynamic investigation requires much more CPU and computation time. For the purpose of studying the complicated global dynamics, the reduction approach is applied to simplify the complexity of connected problem. This work details the coupling technique and the identification of dynamic compartment of transmission system, from a known dynamic response of distinct multibody subsystems. The identification of transmission system was built by joining subsystem using the Frequency Response Function (FRF). This paper discusses the Frequency Based Sub-structuring (FBS) and the condensation methods. A description of these techniques and their importance were displayed. This approach was tested on a discrete system describing a dual stage reducer using receptance coupling. A parametric study was made to determine the sensitivity of the sub-structuring method by varying different parameters. In addition, the sensibility of random perturbation of coupling stiffness on the sub-structuring method was studied. The achieved results obtained by the coupling and the condensation approach were evaluated. The impact of reducer properties on subsystem response and the effect of neighbor parameter system on condensation methods were discussed. A great correspondence is shown between the simulated coupling technique and the full system results.