Advances in Steam Turbines for Modern Power Plants

Part I Steam Turbine Cycles and Cycle Design Optimization 1

1 Introduction to steam turbines for power plants 3

1.1 Features of steam turbines 3

1.2 Roles of steam turbines in power generation 4

1.3 Technology trends of steam turbines 6

1.4 The aim of this book 8
References 9

2 Steam turbine cycles and cycle design optimization: the Rankine cycle, thermal power cycles, and IGCC power plants 11

2.1 Introduction 11

2.2 Basic cycles of steam turbine plants 11

2.3 Types of steam turbines 23

2.4 Various steam turbine cycles and technologies to improve thermal efficiency 29

2.5 Conclusion 40
References 40

3 Steam turbine cycles and cycle design optimization: advanced ultra-supercritical thermal power plants and nuclear power plants 41

3.1 Introduction 41

3.2 A-USC thermal power plants 41

3.3 Nuclear power plants 48

3.4 Conclusion 55
References 55

4 Steam turbine cycles and cycle design optimization: combined cycle power plants 57

4.1 Definitions 57

4.2 Introduction to combined cycle power plants 59

4.3 Combined cycle thermodynamics 60

4.4 Markets served 75

4.5 Major plant systems overview 77

4.6 Combined cycles trends 90

4.7 Conclusion 91
References 91

5 Steam turbine life cycle cost evaluations and comparison with other power systems 93

5.1 Introduction 93

5.2 Cost estimation and comparison with other power systems 94

5.3 Technological learning 96

5.4 The modeling of technological learning 98

5.5 Conclusions 104
References 104

Part II Steam Turbine Analysis, Measurement and Monitoring for Design Optimization 107

6 Design and analysis for aerodynamic efficiency enhancement of steam turbines 109

6.1 Introduction 109

6.2 Overview of losses in steam turbines 109

6.3 Overview of aerodynamic design of steam turbines 114

6.5 Future trends 123

6.6 Conclusions 124
References 125

7 Steam turbine rotor design and rotor dynamics analysis 127

7.1 Categories of steam turbine rotor vibration 127

7.2 Mechanical design of steam turbine rotors 137

7.3 Measurement of, and guidelines for, rotor vibration 148
References 150

8 Steam turbine design for load-following capability and highlyefficient partial operation 153

8.1 Introduction 153

8.2 Solution for grid code requirement 155

8.3 LFC of thermal power plants 158

8.4 Current capacity of thermal power governor-free operation and LFC 159

8.5 Over load valve 160

8.6 Conclusion 164
References 164

9 Analysis and design of wet-steam stages 165

9.1 Introduction 165

9.2 Basic theory and governing equations 171

9.3 Numerical methods 177

9.4 Measurement methods 194

9.5 Design considerations 207
Acknowledgments 210
Notation 210
Greek symbols 211
Subscripts 211
References 211

10 Solid particle erosion analysis and protection design for steam turbines 219

10.1 Introduction 219

10.2 Susceptible area of erosion 219

10.3 Considerations on boiler design and plant design 221

10.4 Considerations on turbine design and operation mode 222

10.5 Result of erosion 225

10.6 Considerations of parameters on erosion and countermeasure 234
Conclusions 238
References 239

11 Steam turbine monitoring technology, validation, and verification tests for power plants 241

11.1 Introduction to power plant testing and monitoring 241

11.2 Performance type testing 243

11.3 Steam turbine component-type testing 253

11.4 Steam turbine monitoring 257

11.5 Summary 259

11.6 Power plant testing—a look ahead 259
References 260

Part III Development of Materials, Blades and Important
Parts of Steam Turbines 261

12 Development in materials for ultra-supercritical (USC)
and advanced ultra-supercritical (A-USC) steam turbines 263

12.1 Introduction 263

12.2 Efficiency improvement of ultra-supercritical and advanced ultra-supercritical turbines 265

12.3 Material development for ultra-supercritical steam turbines 267

12.4 Material development for advanced ultra-supercritical steam turbines 272
Conclusions 277
References 278

13 Development of last-stage long blades for steam turbines 279

13.1 Introduction 279

13.2 Design space for last-stage long blade development 281

13.3 Main features of modern last-stage blades 283

13.4 Design methodology for last-stage long blades 284
Additional descriptions on water droplet erosion analysis and protection design

13.5 Model turbine tests and measurements 298

13.6 Conclusions 303
References 304

14 Introduction of new sealing technologies for steam turbines 307

14.1 Introduction 307

14.2 Flowpath interstage seals 309
Conclusions 319
References 319

15 Introduction of advanced technologies for steam turbine bearings 321

15.1 Geometry of oil-film bearing 321

15.2 Bearing design 326

15.3 Journal bearing testing 348

15.4 Thrust bearing testing 362

15.5 Bearing coating materials 365

15.6 Conclusions 376
Acknowledgments 377
References 378

16 Manufacturing technologies for key steam turbine parts 381

16.1 Introduction 381

16.2 Manufacturing documentation 382

16.3 Castings and forgings 383

16.4 Casings 383

16.5 Rotors 385

16.6 Blade manufacture 388

16.7 Inspection technologies 391

16.8 Conclusion 392
References 393

Part IV Turbine Retrofitting and Advanced Applications in Power Generation 395

17 Steam turbine retrofitting for the life extension of power plants 397

17.1 Comprehensive maintenance planning and new technologies for steam turbine retrofitting 397

17.2 Age deterioration and lifetime of the steam turbine 397

17.3 Outline of retrofitting for life extension 412

17.4 Technology for higher efficiency and other benefits 424

17.5 Summary 435
References 436

18 Steam turbine retrofitting for power increase and efficiency enhancement 437

18.1 Overview 437

18.2 Nomenclature 437

18.3 Introduction 438

18.4 Improvement of plant performance 440

18.5 Key development processes 444

18.6 High-pressure and intermediate-pressure turbine retrofits 446

18.7 Low-pressure turbine retrofits 446

18.8 Summary 453
References 453

19 Advanced geothermal steam turbines 455

19.1 Introduction 455

19.2 Construction of modern geothermal steam turbines 464

19.3 Technologies to enhance reliability of geothermal steam turbines 473

19.4 Technologies to enhance performance of geothermal turbines 477

19.5 Operational experiences and lessons learned 480

19.6 Future view of geothermal power generation and challenges 485
References 485

20 Steam turbines for solar thermal and other renewable energies 487

20.1 Introduction 487

20.2 Pilot plant of solar thermal and biomass binary generation system in Japan 487

20.3 The steam turbine for solar thermal technology 488

20.4 Steam turbine for organic Rankine cycle 493

20.5 Future applications 497
References 498

21 Advanced ultra-supercritical pressure (A-USC) steam turbines and their combination with carbon capture and storage systems (CCS) 501

21.1 Introduction 501

21.2 Advanced ultra-supercritical turbine 502

21.3 Carbon capture technology 502

21.4 Combination of advanced ultra-supercritical turbine and CCS 510
Conclusions 519
References 519

22 Steam turbine roles and necessary technologies for stabilization of the electricity grid in the renewable energy era 521

22.1 Introduction 521

22.2 The issue of the renewable energy era 522

22.3 Requirements of the steam-turbine power-generation system 531

22.4 Innovation and future technologies 535
References 536
Index 539

23. Conclusions