Thermal Deformation Analysis of Automotive Disc Brake Squeal

Automotive disc brake squeal has been a major concern in warranty issues and a challenging problem for many years. A variety of tools have been developed which include both experimental studies and numerical modelling technique to tackle the problem. The aim of this project is to develop a val...

Full description

Saved in:
Bibliographic Details
Main Author: Hassan, Muhammad Zahir
Format: Thesis
Published: 2009
Subjects:
Online Access:http://eprints.utem.edu.my/4132/
http://eprints.utem.edu.my/4132/1/Thermal_Deformation_Analysis_of_Automotive_Disc_Brake_Squeal.pdf
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Automotive disc brake squeal has been a major concern in warranty issues and a challenging problem for many years. A variety of tools have been developed which include both experimental studies and numerical modelling technique to tackle the problem. The aim of this project is to develop a validated thermo-mechanical finite element model considering both the mechanical structural compliance and thermal effects in the dynamic instability of a disc brake system leading to squeal. A key issue in the process is to investigate the structural deformation of the brake components due to the combined effect of thermal expansion and contact loading between pad and disc when subjected to temperature change during a typical braking cycle. A new methodology is introduced whereby a fully coupled transient thermo-mechanical analysis is carried out to provide the temperature and contact distributions within the brake before executing an instability analysis using the complex eigenvalue method. A case study is carried out based on a typical passenger car brake as it undergoes a partial simulation of the SAE J2521 drag braking noise test. The actuation pressure, coefficient of friction and vehicle travelling speed are all considered to derive the temperature dependent contact pressure distributions making allowance for the “rotating heat source” effect. An experimental investigation using a brake dynamometer is also carried out to measuring the squealing noise and thermal deformation which leads to a validation of the results predicted by the numerical modelling. It is demonstrated that the fully coupled thermo-mechanical FE model enhances understanding of the time dependent non-linear contact behaviour at the friction interface. This, in turn, demonstrates the fugitive nature of brake squeal through the system eigenvalues that appear and disappear as a function of temperature throughout the braking period. Parametric studies on the geometrical effect and materials of brake components determine the contribution of each of these factors to brake squeal. The approach therefore can be use as a predictive tool to evaluate disc brake squeal using finite element method.