Investigation & optimization of passenger car brake squeal phenomenon using Finite element analysis and design of experiments

Brake squeal phenomenon has posed a significant challenge for car manufacturing and rail transport companies over the course of many years. In recent years, addressing this issue has become increasingly critical in the evaluation of car brake systems, and this issue has led to significant after-sales service costs for automobile companies. In the frequency domain, vibrations ranging between ۱۰۰۰ and ۲۰۰۰۰ Hz are termed brake squeal. Such vibrations generate an irregular, low-pitched sound typically heard at low speeds, ranging from approximately ۶ to ۶۰ revolutions per minute (rpm), persisting until the vehicle comes to a complete stop. The geometry of the brake pads stands out as one of the most influential parameters in generating the brake squeal sound. This research aimed to identify an optimal geometry for the brake pads with the objective of minimizing the possibility of brake squeal occurrence. Initially, a finite element analysis of the brake system was developed using an innovative approach and the complex eigenvalue analysis was performed, which encompassed parameters such as the maximum damping ratio and the number of unstable modes. Subsequently, variations were made to both the geometry of the brake pad and the friction coefficient to investigate their impact on the instability of the brake system. To examine the influence of the input variables on the analysis outputs, a design of experiments was employed, utilizing the factorial design method. Finally, employing variance analysis, mathematical relationships were derived for each of the output variables based on the input parameters.

کلیدواژه ها:

Finite Element Method (FEM) ، Brake Squeal ، Vibration Analysis ، Complex Eigenvalue Analysis (CEA)