Fluid Machinery and Fluid Mechanics (eBook)

FOREWORD 6
Table of Contents 7
Heat Transfer in an Automotive Turbocharger Under Constant Load Points: an Experimental and Computational Investigation 11
1 Introduction 12
2 Experimental Investigation 12
3 Test Results 13
4 One-Dimensional Model 15
5 Model Results And Validation 16
6 Conclusion 17
Acknowledgements 17
References 17
Multi-Scale Thermal Measurement and Design of Cooling Systems in Gas Turbine 18
1 Introduction 18
2 Multi-scale Thermal Design 18
3 Macro-Scale Cooling Technology 19
4 Micro/Nano-SCAle MeAsurement Schemes 20
5 Multi-SCAle Thermal analysis 21
6 Multi-scale Optimal Thermal Design 22
7 Summary 23
References 23
Reduced Size Bi-Flow Centrifugal Pump as Ventricular Assist Device for End-Stage Patients 24
1 Introduction 24
2 Centrifugal Pump Design 25
3 Results And Discussion 26
4 Cfd Analysis 27
5 Conclusion 28
Acknowledgements 28
References 28
Experimental Investigation of Wall Pressure Fluctuations in Axial Flow Fans with Different Swept 30
1 Introduction 30
2 Experimental Set Up 31
3 Numerical Simulations 33
Geometry and meshing 33
4 Results and Discussion 34
Acoustics results 34
Overall characteristics 34
5 Wall Pressure Measurement 35
6 Conclusion 35
References 35
Meso and Macro-Scales Fluid Flow Simulations with Lattice Boltzmann Method 37
1 Introduction 37
2 Lattice Boltzmann Method 38
3 Boundary Conditions 39
3.1 Bounce Back 39
3.2 Boundary Condition With Known Velocity 39
3.3 Open Boundary Condition 40
4 Force Term and other Physics 40
5 Simulation Results 40
6 Conculuding Remarks 41
References 42
Engineering Flow Performance by Local Dynamics: Theories and Applications 43
1 Introduction 43
2 Local Dynamics on Boundary at LargE Reynolds number 44
2.1 On-Wall Local Dynamics at Large Re 44
2.2 Boundary Vorticity Flux 44
2.3 Boundary Layer Separation and BVF Peaks 45
3 Aerodynamic Forces by Vortical Structures 46
3.1 General Theory 46
3.2 Steady Aerodynamics: Vortex-Force Theory 47
3.3 Unsteady Aerodynamics: Vorticity Moment Theory 48
3.4 Force and Moment by Boundary Vorticity Flux 49
4 Applications 49
4.1 BVF as Marker of Strong On-Wall Local Events 49
4.2 Airfoil Flow Diagnosis and Optimal Design 50
4.3 BVF-Based Compressor Rotor Blade Design 51
5 Concluding Remarks 51
References 52
One-Dimensional Analysis of Full Load Draft Tube Surge 54
1 Introduction 54
2 Analytical model 55
3 Discussions on instabilities with a large sound velocity 57
3.1 Diffuser Effect of the Draft Tube 57
3.2 Swirl effect 58
3.3 Energy Balance 58
4 Numerical Results 59
4.1 The Case with Infinite SoundVelocity in Penstock 59
4.2 The Case with Finite Sound Velocity in Penstock 61
5 Conclusion 65
Acknowledgements 66
References 66
Future Aspects and Developments for Advanced CO2-Free Power Station Technologies 67
1 Introduction 67
2 Importance of CO2-Emissions 67
3 CO2-Reducing Measures 69
Gas Turbine Technology 70
Steam Turbine Technology 72
Project Coordination 74
4 Summary and Conclusion 74
Acknowledgements 74
References 75
Numerical Analysis of Impeller-Volute Tongue Interaction and Unsteady Fluid Flow in a Centrifugal Pump 76
1 Introduction 77
1.1 Numerical techniques 77
1.2 Results and discussions 78
1.3 Velocity Vector 79
1.4 Impeller / volute tongue interaction 79
2 Conclusions 81
References 81
A Procedure for the Unsteady Characterization of Turbochargers in Reciprocating Internal Combustion Engines 82
1 Introduction 82
2 Experimental and Modelling Tools 83
2.1 Engine Test Bench 83
2.2 1D-Wave Action Model 84
3 Research on Compressor Unsteadiness 84
4 Research on Turbine Unsteadiness 87
5 Summary and conclusions 89
Acknowledgements 89
References 89
Cavitation and Turbopump Hydrodynamics Research at Alta S.P.A. and Pisa University 90
1 Introduction 90
2 Experimental Activities 91
Test facility 91
Characterization of space rocket inducers 93
Cavitation and thermal effects on hydrofoils 93
Visual characterization of cavitating flows 94
Current and future work 95
3 Analytical and Numerical Activities 95
Development of cavitation models for CFD codes 95
Rotordynamic analytical models of cavitating inducers 95
Reduced order model of inducer flow and performance 96
4 Conclusions 97
Acknowledgements 97
References 97
Decelerated Swirling Flow Control in the Discharge Cone of Francis Turbines 99
1 Introduction 99
2 Swirling Flow Apparatus 100
3 Swirling Flow Design and Analysis 101
4 Vortex Breakdown Mitigation 103
5 Conclusions 105
Acknowledgements 105
References 105
Hydraulic Oscillations Caused by the Earthquake 107
1 Introduction 108
2 Case studies 108
3 The Approach 109
4 The Tools for Hydraulic Analysis 109
5 CASE I: The Bottom Outlet Of An Existing Dam 110
6 CASEII: Low-Head Hydropower Plant 112
7 Conclusions 114
Acknowledgements 115
References 115
A Numerical Investigation of the Effect of End-Wall Boundary Layer Skew on the Aerodynamic Performance of a Low Aspect Ratio, High Turning Compressor Cascade 117
1 Introduction 118
2 Compressor cascade 118
3 Inlet boundary layer profiles 118
4 Numerical method 120
5 Results and discussion 120
5.1 Limiting Streamlines on End-Walls and Blades 120
5.2 Local Results 121
5.3 Pitchwise Averaged Results 121
5.4 Pitch-and Spanwise Averaged Results 122
6 Comparision with Previous Work 123
References 123
Design and Analysis of a Radial Turbine with Back Swept Blading 125
1 Introduction 126
2 One-Dimensional Performance 126
3 Numerical Model Validation 127
4 Results and Discussions 128
4.1 CFD Results 128
5 FEA Results 129
6 Conclusions 130
Acknowledgements 131
References 131
Swirl Flow and Heat Transfer Through Square Duct with Twisted Tape Insert 132
1 Introduction 132
2 Experimental apparatus 133
3 Mathematical model 134
4 Data reduction 135
5 Results and discussion 135
6 Conclusions 138
References 138
Multi-Objective Automated Optimization of Centrifugal Impeller Using Genetic Algorithm 140
1 Introduction 140
2 Aerodynamic Optimization Design System 141
2.1 MOGA 141
2.2 NURBS blades profile parameterizationand Objective function evaluation 142
2.3 Optimization flow chart 143
3 Optimization design application 143
4 Conclusions 146
References 146
Axisymmetric Weakly Compressible Transient Pipe Flow and Water Hammer Control 147
1 Introduction 148
2 General Formulations 149
2.1 Model Flow and Governing Equations 149
2.2 Assumptions and Nondimensionalization 149
2.3 On the Elasticity of Pipe Wall 150
3 Perturbation Analysis 150
3.1 Perturbation Expansion 150
3.2 Leading-Order Solutions 151
3.3 The Pressure Evolution at the Valve 152
4 Numerical Validations 152
5 Water hammer control Strategies 153
6 Conclusions 154
Acknowledgements 154
References 154
Research on the Optimization Method of Impeller Meridional Contour and 3-D Blade 155
1 Introduction 155
2 Impeller Parameterization method 156
3 Objective Function 157
4 Artificial Neural Networks 157
5 Impeller Optimization 158
5.1 3-D blade 158
5.2 Meridional Contour 159
6 Discussion 161
7 Conclusion 161
Acknowledgements 161
References 161
LDV and PIV Techniques Applied to Turbomachinery Geometry Constrains 163
1 Introduction 163
2 LDV and PIV Measurement Comparisons 164
3 Diffuser Flow Studies with Rotor Stator Interactions 167
4 Conclusions 168
Acknowledgements 168
References 170
Limiting Streamlines Measurement in Contra-Rotating Axial Flow Pump 171
1 Introduction 171
2 Experimental Apparatus 171
3 Experimental Results and Discussion 173
3.1 Flow behavior at design flow rate of Q=70 l/s 173
3.2 Flow behavior at partial flow rate of Q= 28 l/s 174
4 Concluding Remarks 176
References 176
Experimental Modeling of Polluted Air Dispersion in Street Canyons of Metropolitan 177
1 Introduction 177
2 Measurement Set-Up 177
2.1 Wind-tunnel for atmospheric condition 177
2.2 Physical modeling 178
3 The Technic of Measurement 178
3.1 The source of smoke 178
3.2 Velocity 178
3.3 The detail modeling 179
4 The Result of the Urban Canyon 179
4.1 H2 = 1B 179
4.2 H2 = 2B 180
4.3 H2 = 3B 180
4.4 H2 = 4B 181
4.5 H2 = 5B 181
4.6 Occurrence of vortex side by building 181
5 Future Work 182
Acknowledgements 182
References 182
PIV Study of Tip Leakage Flow in Linear Compressor Cascade 183
1 Introduction 183
2 Cascade Model 184
3 Experiment Techniques 184
4 Data Analysis 185
5 Results and Discussion 185
5.1 Inlet flow velocity 185
5.2 Tip clearance size 186
5.3 Inlet flow directions 186
5.4 Winglets in two directions 187
5.5 Downstream leakage vortex 188
6 Conclusion 188
Acknowledgements 188
References 188
Study on Cavitating Turbulent Flow around a Hydrofoil 189
1 Introduction 189
2 Experimental Setup 190
2.1 Water tunnel 190
2.2 Hydrofoil 190
2.3 High-speed visualization 190
2.4 PIV setup 190
3 Results and Discussion 191
3.1 Incipient cavitation (s=1.86) 191
3.2 Sheet cavitation (s=1.4) 191
3.3 Cloud cavitation (s=1.02) 192
3.4 Supercavitation (s = 0.7 and 0.4) 193
4 Conclusions 193
Acknowledgements 194
References 194
Microchannel Heat Sinking: Analysis and Optimization 195
1 Introduction 196
2 Microchannel Model 197
3 Numerical Methods 197
4 Optimization Techniques 198
4.1 Design variables and objective functions 198
4.2 Surrogate construction 198
4.3 Multi-objective (MOEA) 198
5 Results and Discussion 198
6 Conclusion 199
Acknowledgements 199
References 199
A Numerical Simulation of a Flow in Pem Fuel Cell Stack Using Lattice Boltzmann Method 201
1 Introduction 201
2 Lattice Boltzmann Method 202
3 Lattice Boltzmann Equation for Reacting Flow 202
4 Modeling and Assumptions 203
5 Numerical Result and Discussion 203
6 Conclusions 203
Acknowledgements 204
References 204
Simulation of Gas Flow in a Microchannel by Lattice Boltzmann Method 205
1 Introduction 205
2 Lattice Boltzmann Equation with Multiple Relaxation Times 206
3 Kinetic Boundary Condition for the Lattice Boltzmann Equation 207
3.1 The combined bounce-back and specular-reflection boundary condition 207
3.2 Relaxation time in LBE 207
4 Numerical Results 208
4.1 Planar couette flow 208
4.2 Force-driven poiseuille flow 209
5 Conclusions 210
Acknowledgements 210
References 210
Numerical Solution of Navier-Stokes Equations for Separating and Reattaching Flow over a Double Steps Expansion and Contraction 211
1 Introduction 211
2 Theoritical and Numerical Disscusion 211
3 Theoritieal Dissension 213
4 Conculusion 214
Acknowledgements 215
References 215
Computation of Several Turbulent Flows with the Des-Sa Model 216
1 Introduction 216
2 DES-SA Model 217
3 Validation of the DES-SA Model 218
3.1 Fully developed plane channel flow 218
3.2 Turbulent flow around a NACA0012 airfoil 219
3.3 Turbulent flow in a centrifugal pump 221
4 Discussions and Conclusion 222
Acknowledgements 223
References 223
Comparative Study of Turbulence Models in Separated-Attached Diffuser Flow 225
1 Introduction 225
2 Numerical Method 226
3 Turbulence Models 227
3.1 Spalart-allmaras model (Sparlart et al. 1992) 227
3.2 Standard k - e model (Wilcox 2006) 227
3.3 Wilcox (2006) k - . model (Wilcox 2006) 227
3.4 SST k-. model (Menter 1994) 227
3.5 v2 - f model (Durbin 1995) 228
4 Results and Analysis 228
5 Conclusions 230
References 230
Simulating the Blood Flow for the Aorta with a Stenosis 231
1 Introduction 231
2 Physical Model 232
3 Simulation Methods 232
3.1 Basic assumptions 232
3.2 Basic equations 232
3.3 Boundary conditions 232
4 Results & Consideration
4.1 Flow pattern analysis for steady-state calculation 233
4.2 Unsteady flow behaviors 234
5 Concluding Remarks 236
Acknowledgements 236
References 236
Through Flow Models for Engine Turbocharging and Exhaust Heat Recovery 237
1 Introduction 237
2 Engine IES Methodology 238
2.1 Turbo charging and heat recovery 238
2.2 Integrated energy system methodology 239
3 Turbocharger Compressor Through Flow Model 240
3.1 Mathematical model 240
3.2 Model validation 241
4 Turbine Through Flow Model of a Turbocharger or Turbogenerator 241
4.1 Mathematical model 241
4.2 Model validation 242
5 Conclusions 243
Acknowledgements 243
References 243
Study on the SealLeakage of Turbocharger 244
1 Sealing Structure 244
2 Seal Leakage Rate Computation 245
3 Main Structural Parameters Effects on the Seal Leakage Rate 245
4 Analysis of Differences Between Computation and Test 245
5 Effects of Operating State Conditioning Ways on the Leakage Rate Measurement 247
6 Conclusions 247
References 247
Study on the Pre-Tightening Force About the Nut of the Turbocharger Shaft 248
1 The Status Quo of the Pre-Tightening About Nut on the Shaft of Turbocharger 248
1.1 Torque moment method 249
1.2 Rotary angle method 249
1.3 Mark method 249
1.4 Pre- stretching method 249
2 Modeling 249
2.1 Analysis of the formation mechanism on pre-tightening force 249
2.2 Modeling 250
2.3 Parameters 250
3 Calculated examples 251
4 Conclusions 251
Acknowledgements 251
References 251
Vibration Property Analysis of Turbocharger Turbine Blade Under Different Loads 252
1 Introduction 252
2 Prestressed Modal Analysis 252
2 Dynamic Stress Test 254
2.1 Test principle 254
2.2 Results and analysis 254
3 Conclusions 255
References 255
A Method to Solve the Problem of the Application of Ti-AI Turbine 256
1 Introduction 256
2 Connecting Structure of the Ti-AI Turbine 256
3 Stress Simulation of Connecting Part 257
4 Verify the Reliability 258
5 Conclusions 258
Acknowledgements 258
References 258
A Study on Rotor Blades for a Two-Stage Jet Fan 259
1 Introduction 259
2 Rotor Blade 260
3 Experimental Apparatsus and Method 260
3.1 Test jet fan and measurement system 260
3.2 Parameters 261
4 Results and Discussion 261
4.1 Experimental performance 261
4.2 Internal flow 263
4.3 Numericalsimulation for consideration 263
5 Conclusions 264
Acknowledgements 264
References 264
Flow Characteristics in aCross-Flow Fan with Various Design Parameters 265
1 Introduction 265
2 Theoretical Background 266
3 Numerical Analysis 267
4 Experiments 267
5 Results and Discussion 268
6 Conclusions 271
References 271
Determination of an Optimum Orbiting Radius for an Oil-Less Scroll Air Compressor 272
1 Introduction 273
2 Conceptual Design 273
2.1 Basic structure of scroll air compressor 273
2.2 Scroll wrap configuration factors 273
2.3 Design conditions 274
2.4 Effects of orbiting radius on scroll configuration 274
3 Performance Analysis and Discussions 274
3.1 Volume diagram 274
3.2 Pressure and gas force 275
3.3 Dynamics of Moving Elements 276
3.4 Calculation Results 276
4 Conclusions 277
References 277
Studies on Moving Coil Linear Compressor Used for Refrigerator 278
1 Introduction 278
2 System Models 279
3 Experiment RIG 280
4 Results and Discussion 280
4.1 Frequency features oflinear compressor without load 280
4.2 The effect of spring stiffness 281
5 Conclusion 282
Acknowledgment 282
Reference 282
Two-Zone Modeling Prediction Method of Centrifugal Compressor Performance 283
1 Introduction 284
2 Outline of Two-Zone Modeling Method 284
3 Validation Study of Two-Zone Modeling 286
4 Conclusions 288
Acknowledgements 288
References 288
Effect of Swept Blade on Performance of a Small Size Axial Fan 289
1 Introduction 289
2 Swept Fans and Grid Generation 290
3 Numerical Method 290
4 Results 291
4.1 Pressure and efficiency of the fans 291
4.2 Aeroacoustic performance 292
5 Conclusions 293
Acknowledgements 294
References 294
Multi-Objective Optimization of Blood-Pump with Conical Spiral Groove Bearings 295
1 Introduction 295
2 Optimization of Blood-Pump Geometry 296
2.1 Design methodology 296
2.2 Evaluation function 296
2.3 Crossover and mutation 296
3 Numerical Analysis 297
3.1 Methodology 297
3.2 Evaluation of blood damage 297
4 Results and Discussions 297
4.1 Optimized impeller 297
4.2 Pump characteristics 298
4.3 Thrombus 298
4.4 Hemolysis 298
4.5 Blood damage 299
5 Conclusions 300
Acknowledgements 300
References 300
Analysis of Unsteady Flow in a Radial Diffuser Pump 301
1 Introduction 301
2 Numerical and Experiemtal Setups 302
2.1 Pump geometry 302
2.2 Numerical simulation setup 302
2.3 LDV Measurements 302
2.3.1 LDV test stand 302
2.3.2 Data postprocessing 303
3 Results 303
4 Conclusions 306
References 306
Design and Research of Vertical Multistage Barrel Condensate Pump 307
1 Introduction 307
2 Technical Analysis 307
2.1 Unsatisfactory NPSH 308
2.2 Low efficiency 308
2.3 Poor reliability and short service life 308
3 Prototype Design 308
3.1 Structure design of prototype 308
3.2 Optimal design of hydraulic elements 309
3.3 Design of axial force balancing device 309
3.4 Design of sealing device 309
4 Contrastive Analysis on the Running Results 309
5 Conclusions 309
References 310
Influence of Support Shapes on the Efficiency of Bulb Tubular Pumps 311
1 Introduction 311
2 Model Pump System 312
3 Computational Method 312
3.1 Mathematical model 312
3.2 Boundary conditions 312
4 Comparision of Different Schemes 313
5 Results and Discussion 313
6 Conclusions 314
Acknowledgements 314
References 315
Computing Critical Speeds for Multiple-stage Centrifugal Pumps with Dependent Support Properties 316
1 Introduction 316
2 The In Fluence of Bearing Stiffness on Critical Speeds of Multiple-Stage Centrifugal Pump Rotor 317
3 Bearing Model 317
4 Calculation of the Critical Speeds 318
5 Summary 318
Acknowledgements 318
References 318
Numerical Investigation on Impeller-Volute Interaction In a Low Specific Speed Centrifugal Pump with Tongue Profile Variation 320
1 Introduction 320
2 Model Description and Numerical Method 321
3 Effect of Tongue Profile VARIATION on Pump Performance 322
4 Effect of Tongue Profile Variation on pump flow field 323
5 Conclusions 324
Acknowledgements 324
References 324
Experimental Study on a Direct Drive Turbine for Wave Power Converter System 326
1 Introduction 326
2 Experimental Apparatus and Test Thrbine 327
3 Time Serial Output Data 328
4 Performance by the Variation of Wave Height 328
5 Performance by the Variation of Wave Period 329
6 Performance by the Configuration of Attached Devices at the Turbine Front and Rear Entrance 329
7 Visualization oflnternal Flow in the Nozzle Passages 330
8 Conclusions 331
References 331
Determination of Optimum Nozzle Shape of a Direct Drive Turbine by CFD Analysis 332
1 Introduction 332
2 Direct Drive Turbine for Wave Energy Converter 333
3 Configuration of Nozzleand Runner 333
4 Numerical Analysis Method 334
5 Performance Characteristic Curves 334
6 Output Power Analysis 334
7 Velocity Vectors and Distributions 335
8 Pressure Contours in the Flow Passage and Pressure Distributons on the Runner Blade 336
9 Conclusions 337
References 337
Comparison of Several Subgrid-Scale Models for Large-Eddy Simulation of Turbulent Flows in Water Turbine 338
1 Introduction 338
2 Mathematics of Large-Eddy Simulation 339
3 Subgrid Scale Models 340
3.1 Smagorinsky Model 340
3.2 Dynamic Model 340
3.3 Wall-Adapting Local Eddy Viscosity Model 341
3.4 Scale-Dependent Dynamic Model 341
4 Results and Discussion 341
5 Conclusions 343
Acknowledgements 344
References 344
Flow Simulation and Performance Prediction of a Kaplan Turbine 345
1 Introduction 345
2 Numerical Simulation of Turbulent Flow Through a Kaplan TurbinE 346
3 Test Kaplan Turbine and Parameters 346
4 Prediction of Performances for Kaplan Turbine 347
5 Simulation of the Flow in Kaplan Thrbine 349
6 Concluding Remarks 350
Acknowledgements 350
References 350
Analysis of Pressure Fluctuation in DraftTube of Kaplan Turbine 351
1 Introduction 351
2 Mathematical ModelandNumerical Approach 351
3 Coputational Condition 351
4 Results and Analysis 352
4.1 Shape of vortex rope in draft tube 352
4.2 Amplitude and frequency of pressure fluctuation at inlet of draft tube 352
5 Conclusion 354
Acknowledgements 354
References 354
Numerical Simulation of Hydraulic Turbine Based on Fluid-Structure Coupling 355
1 Introduction 355
2 Mathematical Model 356
2.1 Basic Equations 356
2.2 Control Equations Under ALE Coordinate 356
3 Geometry Physical Model of Turbine Flowing Parts 356
4 Numerical Computation 357
4.1 Solving Method 357
4.2 Setting Method of Interface 357
4.3 Mesh Partition 357
4.4 Boundary Conditions 357
4.5 Numerical Calculation Results 358
5 Results Analysis and Conclusions 359
Acknowledgements 360
References 360
Numerical Simulation of Drawdown in Pump Sumps 362
1 Introduction 362
2 Multi Phase Flow Studies 363
3 Computational Model Description 363
3.1 Geometry Generation 363
3.2 Boundary & Initial Conditions
4 Results & Discussions
Acknowledgements 366
References 366
Recent Development of Lagrangian Vortex Method and Its Application into Fluid Machinery and Fluid Engineering 367
1 Introduction 368
2 Algorithm of Lagrangian Vortex Method 368
3 Application Example for Simulation of a Mixed Flow Pump Operation 369
4 Application Example for a Coupled Structure and Fluid Analysis 370
5 Conclusion 372
Acknowledgements 372
References 372
Computer Stimulation of Air-Flowed Smashing Process 373
1 Introduction 373
2 Theory Base of the Simulation System 373
3 Building of the Simulation System 374
4 Run of the Simulation System and the Analysis of the Calculate Result 374
5 Summary 375
References 375
Analysis on Modeling Rotor System with Sidling Bearing and Ring Seal by Using FEM 376
1 Introduction 376
2 The Model of Oil Film Bearing 377
3 Dynamic Model of Ring Seal 379
4 Calculation of the Centrifugal Pump Rptor Dynamic Characteristics 379
5 Summmary and Conclusions 380
References 380
Project Support 380
Cavitating Flow Analysis in a Closed Pump Sump 381
1 Introduction 381
2 Governing Equations of Cavitating Two-Phase Flow in Two-Fluid Model 382
3 Simulation of Two-Phase Cavitating Flow in a Closed Model Pump Sump 383
3.1 Parameters of the Model Pump Sump 383
3.2 Boundary Conditions 383
4 Simulation Results 384
4.1 Velocity Magnitude Distribution 384
4.2 Streamline and Velocity Vector 385
4.3 VolumeFraction of the Cavity Phase 386
5 Conclusions 386
Acknowledgements 386
References 386
Aerodynamic Performance of Double-Sided Labyrinth Seals 387
1 Introduction 387
2 Test 388
3 Test results 389
4 Prediction 391
4.1 Analytic Model 391
4.2 Numerical Analysis 391
4.3 Result 392
5 Conclusion 392
Acknowledgements 392
References 392
Study on the Leakage Flow Field in the Shaft Brush Seal of Steam Turbines 393
1 Introduction 393
2 Porous Medium Model 394
3 Computational Model 395
4 Results and Discussions 396
4.1 Flow Fields in the Labyrinth Seal 396
4.2 Flow Field in the Brush Seal 397
5 Conclusions 398
Acknowledgements 398
References 398
Transverse Jets Analysis on High Speed Rotating Body of Revolution 399
1 Introduction 399
2 Numerical Analysis 400
3 Theoritieal Dissension 401
4 Conculusion 403
Acknowledgements 403
References 403
Numerical Investigation of High-Power Synthetic Jet Actuator Flowfield and Its Influence on Vectoring Control 404
1 Introduction 404
2 Numerical Method 405
Flow Configuration And Grid 405
3 Synthetic Jet Actuator Modeling 405
4 The Results and Analysis 405
5 Comparative Analysis 406
6 Conclusions 407
Acknowledgements 408
References 408
Use of CFD for Thermal Coupling in Aeroengine Internal Air Systems Applications 409
1 Introduction 409
2 Conventional FEA Method 409
3 Conjugate Analysis 410
4 Non-Coupled Procedures 410
5 Coupled Approach 410
Multiple CFD Domain strategy 411
Steady CFD Approximation 411
Multiple CFD Model Facility 411
"Energy Equation Only" Option 411
Parallel Computation 411
Coupling Example 411
6 Concluding Remarks 412
Acknowledgements 413
References 413
Optimization of Patterned Grooves Micromixer Using the Design of Experiments 415
1 Introduction 415
2 Numerical Analysis 416
3 Optimization Technique 417
4 Results and Discussion 418
5 Conclusion 419
Acknowledgements 419
References 419
Numerical Study on Mechanical Characteristics of Aerostatic Bearing 421
1 Introduction 421
2 Controlling Equation 422
3 The Model of Numerical Simulation 422
4 The Simulation Results and Discussions 423
5 Conclusion 423
Acknowledgements 424
References 424
Valve Dynamic Characteristic and Stress Analysis of Reciprocating Compressor Under Stepless Capacity Regulation 425
1 Introduction 425
2 Structure and Material 426
3 Fea Model 427
4 Impact in Normal Position 427
5 Stress Affected by AssembleError 429
5.1 Case a: Inclined Unloader 429
5.2 Case b: Inclined Valve Plate 429
5.3 Case c: Inclined Unloader& Valve Plate
6 Unloader Material 429
7 Conclusion 430
Acknowledgements 430
References 430
Influence of the Floating-Ring Bearing Parameters on Stability of Turbocharge Rotor-Bearing System 431
1 Introduction 431
2 Computational Results of Rotor-Bearing System 431
2.1 Influence of Span on Stability 432
2.2 Influence of Width on Stability 433
2.3 Influences of Gaps on Stability 433
3 Conclusions 434
Acknowledgements 435
References 435
Investigation of the Meter Factor of Turbine Meter with Unsteady Numerical Simulation 436
1 Introduction 436
2 Analysis on Theory 437
3 Bearing Drag Torque 438
4 Governing Equation and Simulation Methods 438
4.1 Governing Equation 438
4.2 RNG k - e Turbulence Model 439
4.3 Simulation Method 439
4.4 Meshedmodel and Boundary Condition 439
5 Comparsion Results Between Numerical Simulation and Calibration Experiments 440
5.1 Numerical Simulation Results 440
5.2 Calibration Experiment Research 441
5.3 Comparison Between CFD and Experiment Research 441
6 Conclusions 442
Acknowledgements 442
References 442
Author Index 444