Modeling of automotive drum brakes for squeal and parameter sensitivity analysis

• Published in: Journal of sound and vibration 2006-01, Vol.289 (1), p.245-263
• Main Authors: Huang, Jinchun, Krousgrill, Charles M., Bajaj, Anil K.
• Format: Article
• Language: English
• Subjects: Acoustics; Applied sciences; Drives; Exact sciences and technology; Fundamental areas of phenomenology (including applications); Mechanical engineering. Machine design; Physics; Shafts, couplings, clutches, brakes; Solid mechanics; Structural acoustics and vibration; Structural and continuum mechanics; Vibration, mechanical wave, dynamic stability (aeroelasticity, vibration control...)
• ISSN: 0022-460X; 1095-8568
• DOI: 10.1016/j.jsv.2005.02.007

Many fundamental studies have been conducted to explain the occurrence of squeal in disc and drum brake systems. The elimination of brake squeal, however, still remains a challenging area of research. Here, a numerical modeling approach is developed for investigating the onset of squeal in a drum brake system. The brake system model is based on the modal information extracted from finite element models for individual brake components. The component models of drum and shoes are coupled by the shoe lining material which is modeled as springs located at the centroids of discretized drum and shoe interface elements. The developed multi degree of freedom coupled brake system model is a linear non-self-adjoint system. Its vibrational characteristics are determined by a complex eigenvalue analysis. The study shows that both the frequency separation between two system modes due to static coupling and their associated mode shapes play an important role in mode merging. Mode merging and veering are identified as two important features of modes exhibiting strong interactions, and those modes are likely candidates that lead to coupled-mode instability. Techniques are developed for a parameter sensitivity analysis with respect to lining stiffness and the stiffness of the brake actuation system. The influence of lining friction coefficient on the propensity to squeal is also discussed.