SIMULATION OF DISPLACEMENT SENSITIVE NONLINEAR DAMPERS VIA INTEGRAL FORMULATION OF DAMPING FORCE CHARACTERIZATION

An integral formulation approach for the characterization of a displacement sensitive non-linear damping force is proposed. This method is based on the transformation of the displacement sensitivity characteristic of the damper into a velocity sensitivity characteristic, and then using an integral formulation to obtain the damping force over the velocity range. The response characteristics of a single-degree-of-freedom (DOF) isolator with displacement sensitive non-linear damper is obtained using the proposed formulation. A local equivalent linearization technique based on energy similarity, as well as direct integration is used to obtain simulation results. The transmitted force-time history as well as system transmissibility are compared with previous studies employing the traditional nonintegral approach for damping force formulation. Simulation results are also compared with available experimental results to demonstrate the effectiveness of the proposed method. It is shown that for displacement dependent dampers, the damper force estimated using an integral formulation is the correct and accurate approach for simulation purposes. (C) 1995 Academic Press Limited