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Empirical Characterization of Friction Parameters for Nonlinear Stick-slip Simulation to Predict the Severity of Squeak Sounds
Journal Article
10-06-01-0004
ISSN: 2380-2162, e-ISSN: 2380-2170
Sector:
Citation:
Bayani, M., Nasseri, A., Heszler, V., Wickman, C. et al., "Empirical Characterization of Friction Parameters for Nonlinear Stick-slip Simulation to Predict the Severity of Squeak Sounds," SAE Int. J. Veh. Dyn., Stab., and NVH 6(1):53-69, 2022, https://doi.org/10.4271/10-06-01-0004.
Language:
English
Abstract:
Squeak and rattle (S&R) are nonstationary annoying sounds inside the car
cabin that impose high warranty costs on car manufacturers. The need for taking
S&R preventing measures and the maturity level and cost considerations of
the physical prototypes during the predesign-freeze stages justifies the use of
virtual simulation methods. Squeak is a friction-induced high-frequency sound
that is attributed to the stick-slip friction phenomenon. The importance of the
friction parameters in the squeak severity prognosis is analytically and
experimentally mentioned in the literature. However, studying the variation of
these parameters, as regards the changes in loading and driving conditions, with
the aim of application in virtual simulations has remained limited or too
simplistic. In this work, the rate weakening effect of the friction coefficient
curve was involved in the nonlinear finite element (FE) simulation of stick-slip
events by an exponential decay formulation. The approximated squeak severity by
the virtual simulations for selected material pairs agreed with the empirical
results from a flexural stick-slip test bench. From the empirical stick-slip
data, the dependence of the squeak severity on the friction decay coefficient
and the difference of static and kinetic friction coefficients at low and high
normal loads were observed, respectively. The relativity of friction parameters
on the test conditions demands a dynamic updating of the friction model that can
be achieved by polynomial or exponential approximations. Also the observed
polynomial relationship between the squeak severity and the operational
conditions can be used to estimate the squeak severity from the linear dynamic
simulation results. The outcome of this work can help to better understand the
influence of the friction modelling parameters and their variation as regards
the operational conditions. This can facilitate a more accurate prediction of
squeak risk by employing virtual simulation tools in the pre-design-freeze
stages of car development.