Lukasz Brenkacz is an Assistant Professor and Research Associate at the Institute of Fluid Flow Machinery, Polish Academy of Sciences in Gdansk, Poland. His research foci are on machinery design, the analysis of bearing systems, computer simulations, and experimental diagnostics of rotating machinery.

1 Introduction 11
1.1 Current State of Knowledge 13
1.2 Review of the Literature on Numerical Determination of Dynamic Coefficients of bearings 21
1.3 Review of the Literature on Experimental Determination of Dynamic Coefficients of Bearings 24
1.4 Purpose and Scope of the Work 29
2 Practical applications of bearing dynamic coefficients 34
2.1 Single-degree of freedom system oscillations 39
2.1.1 Constant excitation force 42
2.1.2 Excitation by unbalance 45
2.1.3 Impact of damping and stiffness 53
2.2 Oscillation of mass with two degrees of freedom 57
2.3 Cross-coupled stiffness and damping coefficients 61
2.4 Summary of Chapter 2 66
3 Characteristics of the Research Subject 68
3.1 Basic Technical Data of the Laboratory Test Rig 68
3.2 Analysis of Rotor Dynamics 72
3.3 Analysis of the Supporting Structure 81
3.4 Summary of Chapter 3 85
4 Research Tools 88
4.1 Test Equipment 89
4.2 Test.Lab Software 95
4.3 Samcef Rotors Software 96
4.4 Matlab Software 98
4.5 MESWIR Series Software (KINWIR, LDW, NLDW) 100
4.6 Abaqus Software 102
5 Algorithms for Experimental Determining of Dynamic Coefficients of Bearings 104
5.1 Development of the Calculation Algorithm 104
5.2 Verification of the Calculation Algorithm on the Basis of a Numerical Model 109
5.3 Results of Calculations of Dynamic Coefficients of Bearings 114
5.4 Summary of Chapter 5 118
6 Inclusion of the Impact of an Unbalanced Rotor 119
6.1 Calculation Scheme 120
6.2 Definition of the Scope of Identification 124
6.3 Results of Calculation of Dynamic Coefficients of Bearings Including Rotor Unbalance 126
6.4 Summary of Chapter 6 128
7 Sensitivity Analysis of the Experimental Method of Determining Dynamic Coefficients of Bearings 131
7.1 Method of Carrying Out a Sensitivity Analysis 133
7.2 Description of the Reference Model 134
7.3 Influence of the Stiffness of the Rotor Material 136
7.4 Influence of Uneven Force Distribution on Two Bearings 137
7.5 Changing the Direction of the Excitation Force and its Effect on the Results Obtained 141
7.6 Eddy Current Sensor Displacement Impact Assessment 144
7.7 Calculation Results for an Asymmetrical Rotor 146
7.8 Summary of Chapter 7 149
8 Experimental Studies 153
8.1 Software Used for Processing of Signals from Experimental Research 156
8.2 Software Used for Calculations of Dynamic Coefficients of Bearings 159
8.3 Preparation of Experimental Tests 162
8.4 Implementation of Experimental Research 166
8.5 Processing of the Signal Measured During Experimental tests 172
8.6 Results of Calculations of Dynamic Coefficients of Hydrodynamic Bearings on the Basis of Experimental Research 175
8.7 Verification of Results Obtained 185
8.8 Summary of Chapter 8 187
9 Numerical Calculations of Bearing Dynamic Coefficients 191
9.1 Method of Calculating Dynamic Coefficients of Bearings 191
9.2 Calculation of Dynamic Coefficients of Bearings Using a Method with Linear Calculation Algorithm 202
9.3 Calculation of Dynamic Coefficients of Bearings Using a Method with Non-Linear Calculation Algorithm 209
9.4 Verification of Results Obtained 218
9.5 Summary of Chapter 9 225
10 Comparison of Bearing Dynamic Coefficients Calculated with Different Methods 228
11 Summary and Conclusions 235
References 244
List of important designations 257