Skip to main content

Lund University Publications

LUND UNIVERSITY LIBRARIES

A methodology to simulate the performance of automotive brake systems

Varriale, Francesco LU (2025)
Abstract
Airborne particle emissions from road vehicles represent a significant concern for urban air quality. Among the key contributors to non-exhaust emissions (NEE) are vehicle disc brakes, which have recently been recognized as equally important as exhaust emissions. In disc brake systems, the brake pads are pressed against the rotating disc to decelerate the vehicle. This contact causes wear on the disc and pad surfaces, resulting in debris, some of which becomes airborne and poses health risks when inhaled. Particle emissions from disc brakes are affected by various phenomena at the contact sliding interfaces, including friction, wear, contact temperature, contact pressure, and surface topography. Due to the complexity of accessing the... (More)
Airborne particle emissions from road vehicles represent a significant concern for urban air quality. Among the key contributors to non-exhaust emissions (NEE) are vehicle disc brakes, which have recently been recognized as equally important as exhaust emissions. In disc brake systems, the brake pads are pressed against the rotating disc to decelerate the vehicle. This contact causes wear on the disc and pad surfaces, resulting in debris, some of which becomes airborne and poses health risks when inhaled. Particle emissions from disc brakes are affected by various phenomena at the contact sliding interfaces, including friction, wear, contact temperature, contact pressure, and surface topography. Due to the complexity of accessing the pad-to-disc contact area within the brake system during testing, studying these contact phenomena is challenging. Additionally, experimental investigations require the production of friction materials and brake systems at least in prototype form, which are costly and time-consuming. The objective of this thesis is to develop a simulation-based methodology to enhance the understanding of contact phenomena and to assess the tribological performance of friction materials and brake systems during the early design phase of the project. Additionally, a study is carried out to examine the behaviour of the individual components of a friction material compound in relation to NEE.

Different simulation approaches can be employed depending on the specific aspects being evaluated. A macro-scale approach utilizing finite element analysis (FEA) can be applied to assess the global coefficient of friction (COF) of a disc brake system. The global COF can also be estimated by utilizing 3D friction pvT-maps, which are derived from analysing and filtering experimental data obtained from tests conducted on a reduced-scale dynamometer bench. Conversely, a meso-scale approach using cellular automaton (CA) simulation can be employed to analyse local contact behaviour on the disc and pad surfaces and to examine the influence of single ingredients of a friction material compound. This method is capable of investigating plateau dynamics and its impact on brake system performance.
(Less)
Please use this url to cite or link to this publication:
author
supervisor
opponent
  • Dr. Gramstat, Sebastian, Audi AG, Germany.
organization
publishing date
type
Thesis
publication status
published
subject
keywords
coefficient of friction (COF), Wear, Simulation, Brake performance, Cellular automaton
pages
70 pages
publisher
Department of Mechanical Engineering, Lund University
defense location
Lecture Hall M:E, building M, Ole Römers väg 1, Faculty of Engineering LTH, Lund University, Lund.
defense date
2025-01-31 09:00:00
ISBN
978-91-8104-313-6
978-91-8104-312-9
language
English
LU publication?
yes
id
18bb936f-f04c-45b6-b13f-96f22d5d3088
date added to LUP
2025-01-03 14:16:07
date last changed
2025-04-04 14:38:56
@phdthesis{18bb936f-f04c-45b6-b13f-96f22d5d3088,
  abstract     = {{Airborne particle emissions from road vehicles represent a significant concern for urban air quality. Among the key contributors to non-exhaust emissions (NEE) are vehicle disc brakes, which have recently been recognized as equally important as exhaust emissions. In disc brake systems, the brake pads are pressed against the rotating disc to decelerate the vehicle. This contact causes wear on the disc and pad surfaces, resulting in debris, some of which becomes airborne and poses health risks when inhaled. Particle emissions from disc brakes are affected by various phenomena at the contact sliding interfaces, including friction, wear, contact temperature, contact pressure, and surface topography. Due to the complexity of accessing the pad-to-disc contact area within the brake system during testing, studying these contact phenomena is challenging. Additionally, experimental investigations require the production of friction materials and brake systems at least in prototype form, which are costly and time-consuming. The objective of this thesis is to develop a simulation-based methodology to enhance the understanding of contact phenomena and to assess the tribological performance of friction materials and brake systems during the early design phase of the project. Additionally, a study is carried out to examine the behaviour of the individual components of a friction material compound in relation to NEE.<br/><br/>Different simulation approaches can be employed depending on the specific aspects being evaluated. A macro-scale approach utilizing finite element analysis (FEA) can be applied to assess the global coefficient of friction (COF) of a disc brake system. The global COF can also be estimated by utilizing 3D friction pvT-maps, which are derived from analysing and filtering experimental data obtained from tests conducted on a reduced-scale dynamometer bench.  Conversely, a meso-scale approach using cellular automaton (CA) simulation can be employed to analyse local contact behaviour on the disc and pad surfaces and to examine the influence of single ingredients of a friction material compound. This method is capable of investigating plateau dynamics and its impact on brake system performance.<br/>}},
  author       = {{Varriale, Francesco}},
  isbn         = {{978-91-8104-313-6}},
  keywords     = {{coefficient of friction (COF); Wear; Simulation; Brake performance; Cellular automaton}},
  language     = {{eng}},
  month        = {{01}},
  publisher    = {{Department of Mechanical Engineering, Lund University}},
  school       = {{Lund University}},
  title        = {{A methodology to simulate the performance of automotive brake systems}},
  year         = {{2025}},
}