A Dissertation Submitted to Wuhan University of Technology for the Bachelor Degree

Thermal-Mechanical Coupling Numerical Simulation and Structural Optimization Design of Large Tonnage Vehicle Disc Brake

Student： Zhou You

Supervisor： Deng Jiadong

College： International Education College

Class： Automotive gj 1501

May 24, 2020

Statement of originality of dissertation

I solemnly declare that the dissertation submitted is the research result obtained from my independent research under the guidance of my tutor.This paper does not include any other work that has been published or written by an individual or group, except as specifically cited in the paper.I am fully aware that the legal consequences of this statement are my responsibility.

Author's signature：Zhou You

May 29, 2020

Power of attorney for use of dissertation copyright

The author of this dissertation fully understands the provisions of the university on the protection and use of the dissertation, and agrees that the university shall retain and send the copy and electronic version of the dissertation to the relevant dissertation administration department or institution, and allow the dissertation to be consulted and borrowed.I authorize the provincial excellent bachelor's thesis selection institution to incorporate all or part of the content of this dissertation into the relevant data for retrieval, and the dissertation can be saved and compiled by means of photocopying, reducing or scanning.

This dissertation belongs to 1. Confidentiality，This power of attorney shall apply after 30 years of declassification.

2. No confidentiality囗.

Author's signature: Zhou You, May 29, 2020

Mentor signature: ,

Abstract

In modern society, automobile has become an important tool for people to travel and carry goods, and automobile safety has naturally become a focus of attention. Braking system is an important part of automobile, which can effectively guarantee the safety of automobile. Disc brakes are widely used in various automotive braking systems because of their excellent performance. When the car is braking, the disc brake bears almost all the braking pressure, and the working conditions are bad. In order to ensure the normal operation of the brake, it is very necessary to design the disc brake. Based on the basic parameters of a passenger car, this paper designs its disc brake. Through theoretical calculation, the key design parameters such as braking moment, braking distribution coefficient and structural parameters of brake disc and brake block are obtained, and the shape and size of brake are designed. With the aid of CATIA, the main parts of brake are designed in three-dimensional virtual way, and the three-dimensional models of brake block, brake disc, clamp shell and other parts are established. Finally, with the aid of CAE simulation software ABAQUS, the key parts such as clamp shell and brake disc are simulated and analyzed. Through the static strength analysis of the clamp shell, it is found that the displacement of the clamp shell is large and the stress concentration exists in the braking process, so the structure of the clamp shell is optimized. Through the thermodynamic analysis of the brake disc, it is found that the maximum temperature of the brake disc during braking is not more than 300 C, which shows that the brake disc has good heat dissipation effect and can greatly avoid the thermal degradation caused by the sharp rise of temperature.

Key words : Disc brake; Theoretical design; Three-dimensional modeling; Static simulation analysis; Thermodynamic simulation analysis

Content

Chapter 1 Introduction 6

1.1 The introduction 6

1.2 Disc brake overview 7

1.3 Research status of disc brake 8

1.3.1 Foreign research status 8

1.3.2 Research Status of Domestic Automotive Disc Brakes 9

1.4 Research contents, objectives and technical solutions 10

1.4.1 Basic Contents of Research 10

1.4.2 Research objectives 11

1.4.3 Technical Scheme and Measures 11

Chapter 2 Structure selection and parameter calculation of disc brake 12

2.1 basic parameters of the car 12

2.2 Type selection of disc brake structure 12

2.3 Calculation of key parameters of brake disc 14

2.3.1 Diameter of brake disc 14

2.3.2 Thickness of brake disc 15

2.4 Calculation of key parameters of brake block 15

2.4.1 Working area of friction liner 15

2.4.2 Brake block thickness 16

2.5 Calculation of wear characteristics of friction liner 16

2.6 Calculation of synchronous adhesion coefficient and brake braking torque 18

2.7 Braking strength check 19

Chapter 3 Design and calculation of hydraulic brake driving mechanism 24

3.1 Brake wheel cylinder diameter and brake master cylinder diameter 24

3.1.1 Diameter of brake wheel cylinder 24

3.1.2 Diameter of brake master cylinder 24

3.2 Brake pedal force and pedal travel 25

Chapter 4 Dimensional virtual design of disc brake structure 27

4.1 Introduction to Catia software 27

4.2 3D design and virtual assembly of main components of disc brake 28

4.2.1 3D modeling of clamp housing 28

4.2.2 3D modeling of scaffolds 29

4.2.3 3D modeling of brake disc 30