Measured and estimated friction interface parameters in a nonlinear dynamic analysis

The modelling of nonlinear friction contact interfaces in structural dynamics currently attracts large research interest since the accurate characteristics of the friction interfaces are required in the nonlinear dynamic analysis of assembled structures. For an accurate representation of friction contact interfaces it is important to ensure that a sufficient number of parameters are provided to characterise all aspects of the friction contacts that the measured values are accurate and reliable, and that the contact parameters are interpreted and used correctly in the numerical modelling of the contact interfaces.This investigation focused on three major parameters used in the nonlinear friction contact analysis: (i) the friction coefficient, (ii) the tangential contact stiffness, and (iii) the normal load distribution in the contact. The accuracy of the measured friction input parameters is evaluated and possibilities to obtain reliable normal load distributions for a successful prediction of the measured frequency response function are investigated. Average friction input parameters, based on a large set of experimental data, are introduced, and their effect on the nonlinear resonance response is discussed.

► Evaluation of measurement accuracy and repeatability of 1D friction rig results. ► Averaged friction input parameters for nonlinear analysis. ► Modelling and validation of the nonlinear friction test rig.