Graduation Design (Dissertation) of Wuhan University of Technology

Analysis of Wheel/Rail Contact of Rail Vehicles Based on CAE Modeling

(School): Institute of International Education

Specialty amp; Class: Auto-gj1301

Student name: Wang Kai

Tutor: Duan Fangfang

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Abstract

With the train running speed and carrying capacity continues to improve, accompanied by the worsening of the operating environment of the vehicle，which requires the higher level design of locomotives, railways and etc ，however, wheel and rail as an important part of the connection between the vehicle and the ground parts, wheel and rail contact is the basic train traction, but also the basis of the entire transport. The study of wheel-rail relationship involves many disciplines, and the wheel-rail contact theory is based on the study, wheel and rail contact behavior is its key content.

In this paper, we first introduce the Hertz contact theory and the finite element method for dealing with nonlinear contact problems. On the basis of this, the research on the influencing factors of three - dimensional nonlinear static contact and dynamic contact of wheel and rail is carried out. The finite element model of three - dimensional nonlinear contact of wheel and rail is established by using ABAQUS finite element analysis software. The wheels in the model are tapered TB treads with a 60Kg / m rail and the two rails of the rail base slope are 1:10 and 1:20.

Traditional design method (including Hertz contact theory and elastic Method) problem can not be calculated with high accuracy the wheel-rail contact patch size, shape and stress distribution。The method of calculating the nonlinear contact of three - dimensional wheel - rail with ABAQUS is put forward. The results of static contact analysis show that the nonlinear contact problem of wheel and rail is inevitable, and it is necessary to consider the plastic deformation of the material to be closer to the real situation。By changing the wheel weight, the results show that the contact spot shape and size are changed with the wheel weight. The large-scale finite element model of wheel-rail system is established in dynamic contact analysis. The results show that the influence of wheel-rail contact stress is affected by speed.

Key words: wheel and rail; Hertz contact theory; finite element; ABAQUS software.

CONTENTS

Abstract 3

Chapter 1 Introduction 3

1.1 Background and significance of research 3

1.1 Research status of urban rail transit at home and abroad 5

1.2.1 Summary of domestic research status 5

1.2.2 Summary of overseas research status 5

1.3 Status quo of rolling contact problems in wheel / rail research at home and abroad 6

1.4 Track irregularity 9

1.5 The significance of this study 10

Chapter 2 The basic theory of wheel - rail contact and nonlinear contact finite element 12

2.1 Hertz contact theory 12

2.2 Wheel / rail nonlinear contact finite element method 15

2.3 Comparison and determination of finite element algorithms 16

2.4 Basic assumptions established by the finite element analysis model 18

2.5 Summary of this chapter 19

Chapter 3 The establishment of the bogie model 20

3.1 Introduction to Locomotive Bogies 20

3.2 The creation of various components 21

3.3 Nonlinear simulation of materials 22

3.4 Simplification of the bogie model 24

3.2.1 Bogie force and transmission 24

3.2.2 Bogie simplification model establishment 25

3.5 Summary of this chapter 27

Chapter 4 Modal analysis of bogie simplification model 28

4.1 Modal analysis of locomotive bogie 28

4.1.1 Classification of modal analysis 28

4.1.2 Present situation of bogie modal analysis and its existing problems 28

4.1.3 Modal analysis of the purpose of the study 29

4.2 Bogie sliding and rolling analysis 30

4.2.1Rolling/sliding wheel-rail contact model 30

4.2.2 The quasi-static model of wheel-rail contact with friction 30