Wuhan University of Technology Graduation Design (Thesis)

Design of Rear Torsion Beam Suspension for Dong Feng Peugeot 308

School (Department): School of International Education

Professional class: Automobile Engineering gj1503

Student Name: Fu Xianyu

Supervisor: Fang Zhigang

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Abstract

The main focus of this paper is the design of Dong Feng Peugeot 308 rear suspension. After learning the principles, requirements and design process of the suspension design, the relevant basic design parameters have been set based on the factors such as market status, purpose of the vehicle, the natural vibration frequency of the rear suspension, the stiffness of the suspension, the static deflection, etc. The parameters of the suspension's elastic components, dampers and other basic components have also been set and checked to ensure that the design meets the market demand and operational environment of the model. The three-dimensional model of the suspension was drawn by using the three-dimensional graphics software CATIA, and the rear suspension assembly drawing and part drawing were drawn using AutoCAD. The three-dimensional model of some parts was imported into ANSYS for deformation and stress analysis, which verified that the proposed design meets the requirements.

Key words: torsion beam suspension; three-dimensional model; static analysis

Contents

Chapter 1 Introduction 1

1.1 Research Background and Significance 1

1.1.1 Research Background 1

1.1.2 Research Significance 1

1.2 Research Status of Torsion Beam Suspension 2

1.2.1 Status of Foreign Research 2

1.2.2 Status of Domestic Research 3

1.3 The Main Research Content of This Paper 5

1.4 The Main Technical Route of This Study 5

Chapter 2 Automotive Suspension Overview 7

2.1 Classification of Suspension 7

2.1.1 Independent Suspension 7

2.1.2 Non-independent Suspension 7

2.2 Suspension Design Requirements 8

2.3 Torque Beam Suspension 9

2.3.1 Torsion Beam Suspension Noun Explanation 9

2.3.2 Characteristics of The Torsion Beam Suspension 10

2.3.3 Dong Feng Peugeot 308 Vehicle Rear Suspension 10

Chapter 3 Determination of Main Parameters of Torsion Beam Rear Suspension 12

3.1 Basic Parameters of The Vehicle 12

3.2 Rear Suspension Offset and Static Deflection 13

3.3 Rear Suspension Dynamic Deflection 14

3.4 Rear Suspension Working Stroke 15

3.5 Rear Suspension Stiffness 15

3.6 Suspension Elastic Characteristics 16

3.7 Summary of This Chapter 17

Chapter 4 Design of Suspension Parts 18

4.1 Design of Coil Spring 18

4.1.1 Helical Spring Stiffness 18

4.1.2 Material Selection of Coil Spring 18

4.1.3 Spring Geometry Design 18

4.1.4 Helical Spring Shear Stress Check 20

4.1.5 Spiral Spring CATIA Three-dimensional Model 21

4.2 Design of Damper 21

4.3 3D Modeling of Other Parts of The Rear Torsion Beam Suspension 25

4.4 Summary of This Chapter 27

Chapter 5 Mechanical Analysis of Torsion Beam Suspension Parts 28

5.1 Establish a Mechanical Analysis Model Tree 28

5.1.1 Analysis Tree Overview 28

5.1.2 Analysis Tree Detailed Steps 28

5.1.3 Definition of Materials 29

5.1.4 Dividing The Grid 30

5.1.5 Applying Loads and Constraints 30

5.2 Car Full Load Stationary State 30

5.3 Safety Factor Status 32

5.4 Summary of This Chapter 33

Chapter 6 Summary 34

References 35

Acknowledgement 37

Appendix A 38

Chapter 1 Introduction

• 1. Research Background and Significance

1.1.1 Research Background

Suspension is one of the important assemblies on modern cars that elastically connect the frame (or body) to the axle (or wheel). Its main purpose is to transmit all the forces and moments acting between the wheel and the frame (or the body); to mitigate the impact load transmitted by the road to the frame (or the body), to attenuate the vibration of the bearing system caused by the car, to ensure the car's Smooth ride; ensure the wheel has ideal motion characteristics when the road is uneven and the load varies, and to ensure the steering stability of the car, so that the car can attain high-speed driving ability[1].

As people's demands for ride comfort and handling safety are getting higher and higher, the selection of suspension is becoming more stringent. Choosing a suitable suspension plays an important role in the design of the car. Proper and optimum design of suspension is vital to steering stability and ride comfort. The continuous need of improvement for these requirements has attracted extensive attention of the suspension system researchers.