Elastomere Friction (eBook)

Preface 6
Contents 8
Modelling of Dry and Wet Friction of Silica Filled Elastomers on Self-Affine Road Surfaces 9
Introduction 9
Theory 10
Analysis of Self-Affine Surfaces 10
Hysteresis Friction Simulation 12
Adhesion Friction Fitting 13
Experimental Methods and Proceedings 14
Surface Properties 14
Material Preparation and Properties 16
Friction Experiments and Simulations 16
Results and Discussion 17
Viscoelastic Properties 17
Friction Measurements 24
Adapting Friction Simulation to Wet and Dry Measurements 25
Contact Simulations 27
Conclusions 32
References 33
Micromechanics of Internal Friction of Filler Reinforced Elastomers 35
Introduction 35
Experimental 38
Sample Preparation 38
Multihysteresis Measurements 39
Theory 40
Stress Softening and Hysteresis 42
Hydrodynamic Strain Amplification 44
Constance of Volume 45
Dependence on Temperature 47
Results and Discussion 48
Uniaxial Compression-Tension Test of Unfilled Rubber 48
Adaptation of the Model for Various Filled Rubbers in Tension 48
CB-Filled Rubber in Combined Compression-Tension Test 51
CB-Filled Rubber at Varied Particle Size and Temperature 53
Finite-Element (FE) Simulation of a Rolling GROSCH Wheel 56
Conclusions 58
References 59
Multi-scale Approach for Frictional Contact of Elastomers on Rough Rigid Surfaces 61
Introduction 61
Multiscale Approach 64
Formulation of the Multi-scale Approach 65
Constitutive Model for Elastomers 68
Rough Surface Description 70
Sine Wave 71
Application of the Approximation to a Rough Surface 73
Contact 76
Contact Kinematics and Interface Constraints 76
Numerical Results 79
System and Loading 80
Results on Microscale 81
Meso- and Macroscopic Results 84
True Contact Area 86
Adhesion 90
FEM 91
Adhesion Parameters 93
Numerical Results 94
ThermalEffects 96
Basic Equations 96
Friction Test 98
Conclusions 100
References 100
Thermal Effects and Dissipation in a Model of Rubber Phenomenology 103
Introduction 103
The Standard Rubber Model MORPH 104
Implementation of Thermal Effects 106
Experimental Data for Thermal Effects in Six Rubber Compounds 106
Programs for Simulating Experiments and Identifying All Material Constants 108
Results for Thermal Effects in MORPH Model 110
Reversible Energy and Irreversible Dissipation 117
Large and Small Tensional Cycles 118
Derivation of an Energy Density for Additional Stresses 119
Simulations with New Energy Density 123
Discussion 127
Conclusion 128
References 129
Finite Element Techniques for Rolling Rubber Wheels 130
Introduction 130
Relative Kinematic Framework for Rolling Contact 132
Constitutive Modelling of Rubber 134
Continuum Mechanics Damage Model 137
Pseudo-Elastic Damage Model 138
Treatment of Inelastic Behavior within the ALE Description of Rolling 141
The Fractional-Step Strategy 141
Numerical Methods for Advection Dominated Problems 142
Comparison of Numerical Advection Schemes 146
Numerical Benchmark 149
Treatment of Friction within the ALE Formulation of Rolling Bodies 152
Numerical Examples 158
Grosch Wheel 159
Tire Model 163
Remark to the Computational Effort 165
Summery and Conclusions 166
References 168
Simulation and Experimental Investigations of the Dynamic Interaction between Tyre Tread Block and Road 171
Introduction 171
Modular Tread Block Model 172
Module 1: Dynamic Tread Block Description 174
Module 2: Local Friction Characteristic 178
Module 3: Non-linear Contact Stiffness 180
Module 4: Wear 184
Parameter Identification 185
Identification of Elasticity Modulus and Damping Coefficient 185
Identification of Density 188
Optimisation of Number of Modes 188
Identification of Local Friction Characteristic 189
Identification of Non-linear Contact Stiffness 191
Identification of Wear Coefficients 192
Simulations 193
Stationary Tread Block Behaviour 194
Influence of Wear 195
Dynamic Tread Block Behaviour 196
Comparison with Experiment 198
Rolling Contact 199
Conclusion 203
References 204
Micro Texture Characterization and Prognosis of the Maximum Traction between Grosch Wheel and Asphalt Surfaces under Wet Conditions 207
Introduction 207
Mechanisms of Rubber Friction 209
Maximum Traction under Wet Conditions 209
Advantage of the Grosch Wheel 210
Experimental Investigation of the Process 211
Reproducibility of the Friction Measurement 212
Influence of Wheel Load 214
Influence of Speed and Temperature 216
Influence of Rubber Compound 219
Pavement Roughness Grip and Grip Index 220
The Grip Index 220
Characterization of the Pavement Micro Texture 221
Contact Depth Model 222
Correlation between the Grip Index and Contact Depth Model Descriptors 223
Conclusion 225
References 226
Experimental and Theoretical Investigations on the Dynamic Contact Behavior of Rolling Rubber Wheels 227
Introduction 227
Measurements 228
Moving Test Rig 229
Steady Measurements 230
Unsteady Measurements 232
Rolling Contact Model 235
Efficient Structure Modeling 236
Simulation 241
Identification of Parameters 242
Results and Validations 245
Steady Results 245
Unsteady Results 249
Conclusions 253
References 254
Author Index 256