Projects per year
Systematic experiments have been conducted for an automobile MacPherson corner setup with floating calliper brake at a drum driven suspension and brake test rig. An objective evaluation method is utilised to evince and analyse creep groan events regarding a test matrix of brake pressures and drum velocities. Moreover, interface forces between test rig and corner setup have been measured and evaluated together with characteristic static stiffness curves of the axle elastomer components. For the purpose of transient simulation with virtual evaluation of creep groan, a simplified FE model of the tested system has been elaborated. The computations are performed using an explicit time integration scheme. Two significantly different operating points have been simulated. In addition, a parameter study in terms of the non linear static stiffness curve of the lower control arm hydro bushing is involved.
Parts of the test matrix experiments reveal operational parameter combinations with a clear tendency for creep groan phenomena. If such occur, signatures hinge strongly, but not exclusively, on the brake pressure. The dependence is explainable by different interface force levels which emphasise other operating ranges in the hydro bushing static stiffness curve. This variability results in specifically tuned and/or pronounced natural frequencies and related stick slip cycles. Hence, this component parameter should be considered in a non linear manner within transient simulations. Consequently, computations of dynamic system responses or stick slip oscillations correlate better with comparable experiments.
The introduced FE model will need improvements for more compliance to the tested setup, e.g. concerning modelling and parameters of the suspension strut assembly or regarding non linear damping of the elastomer components. Since tribological conditions are of main relevance, a carefully considered friction model should be implemented into profound studies.
The utilised systematic experimental characterisation procedure for creep groan has already been published. Concerning simulations, a paper about low frequency limits of modal methods has been disclosed. This work provides further experimental investigations of creep groan across a wide range of operational parameter combinations. Moreover, it introduces a simplified vehicle corner FE model and applies promising explicit time integration strategies.
This article deals with investigations of creep groan on vehicle corner level. Both the introduced model and the explicit schemes of time integration in non linear FEA are suitable to reflect a creep groan behaviour comparable to the test rig experiments. Thus, a helpful contribution is made towards accurate, efficient and robust procedures which can be applied for simulative evaluations of automobile brake creep groan.
|Title of host publication||Proceedings of Eurobrake 2018|
|Number of pages||15|
|Publication status||Published - 22 May 2018|
|Event||EuroBrake 2018: Europe's braking technology conference & exhibition - Den Haag, Netherlands|
Duration: 22 May 2018 → 24 May 2018
|Conference||EuroBrake 2018: Europe's braking technology conference & exhibition|
|Period||22/05/18 → 24/05/18|
Fields of Expertise
- Mobility & Production
- 1 Finished
15_005l SimGroan - Simulation on Creep Groan Noise Investigation of excitation mechanism for FEM simulation using experimental data
1/04/15 → 30/03/18
Project: Research project
- 1 Talk at conference or symposium
Manuel Pürscher (Speaker)23 May 2018
Activity: Talk or presentation › Talk at conference or symposium › Science to science