Innovation in Wind Turbine Design

An updated and expanded new edition of this comprehensive guide to innovation in wind turbine design

Innovation in Wind Turbine Design, Second Edition comprehensively covers the fundamentals of design, explains the reasons behind design choices, and describes the methodology for evaluating innovative systems and components.

This second edition has been substantially expanded and generally updated. New content includes elementary actuator disc theory of the low induction rotor concept, much expanded discussion of offshore issues and of airborne wind energy systems, updated drive train information with basic theory of the epicyclic gears and differential drives, a clarified presentation of the basic theory of energy in the wind and fallacies about ducted rotor design related to theory, lab testing and field testing of the Katru and Wind Lens ducted rotor systems, a short review of LiDAR, latest developments of the multi-rotor concept including the Vestas 4 rotor system and a new chapter on the innovative DeepWind VAWT.

The bookis divided into four main sections covering design background, technology evaluation, design themes and innovative technology examples.

Key features:

• Expanded substantially with new content.

• Comprehensively covers the fundamentals of design, explains the reasons behind design choices, and describes the methodology for evaluating innovative systems and components.

• Includes innovative examples from working experiences for commercial clients.

• Updated to cover recent developments in the field.

The book is a must-have reference for professional wind engineers, power engineers and turbine designers, as well as consultants, researchers and graduate students.

Autorentext

PETER JAMIESON is based at Strathclyde University for two days a week acting as a special technical advisor whilst also conducting independent research into wind energy. As a founder member of GL Garrad Hassan's Scottish office and of their Special Projects Department, he is uniquely positioned to offer the highest guidance in the future development of wind energy in the UK and beyond.

Inhalt
Foreword xv

Preface xvii

Acknowledgement xix

Introduction 1

0.1 Why Innovation? 1

0.2 The Challenge of Wind 2

0.3 The Specification of a Modern Wind Turbine 2

0.4 The Variability of the Wind 4

0.5 Early Electricity-Generating Wind Turbines 4

0.6 Commercial Wind Technology 6

0.7 Basis of Wind Technology Evaluation 7

0.7.1 Standard Design as Baseline 7

0.7.2 Basis of Technological Advantage 7

0.7.3 Security of Claimed Power Performance 8

0.7.4 Impact of Proposed Innovation 8

0.8 Competitive Status of Wind Technology 8

References 9

Part I Design Background 11

1 Rotor Aerodynamic Theory 13

1.1 Introduction 13

1.2 Aerodynamic Lift 14

1.3 Power in the Wind 16

1.4 The Actuator Disc Concept 17

1.5 Open Flow Actuator Disc 19

1.5.1 Power Balance 19

1.5.2 Axial Force Balance 20

1.5.3 Froude's Theorem and the Betz Limit 20

1.5.4 The Power Extraction Process 22

1.5.5 Relativity in a Fluid Flow Field 23

1.6 Why a Rotor? 25

1.7 Actuator Disc in Augmented Flow and Ducted Rotor Systems 26

1.7.1 Fundamentals 26

1.7.2 Generalised Actuator Disc 28

1.7.3 The Force on a Diffuser 36

1.7.4 Generalised Actuator Disc Theory and Realistic Diffuser Design 37

1.8 Blade Element Momentum Theory 38

1.8.1 Introduction 38

1.8.2 Momentum Equations 38

1.8.3 Blade Element Equations 40

1.8.4 Non-dimensional Lift Distribution 40

1.8.5 General Momentum Theory 41

1.8.6 BEM in Augmented Flow 42

1.8.7 Closed-Form BEM Solutions 44

1.9 Optimum Rotor Design 46

1.9.1 Optimisation to Maximise Cp 46

1.9.2 The Power Coefficient, Cp 48

1.9.3 Thrust Coefficient 51

1.9.4 Out-of-Plane Bending Moment Coefficient 52

1.9.5 Optimisation to a Loading Constraint 54

1.9.6 Optimisation of Rotor Design and Hub Flow 56

1.10 Limitations of Actuator Disc and BEM Theory 57

1.10.1 Actuator Disc Limitations 57

1.10.2 Inviscid Modelling and Real Flows 58

1.10.3 Wake Rotation and Tip Effect 58

1.10.4 Optimum Rotor Theory 59

1.10.5 Skewed Flow 59

1.10.6 Summary of BEM Limitations 59

References 60

2 Rotor Aerodynamic Design 65

2.1 Optimum Rotors and Solidity 65

2.2 Rotor Solidity and Ideal Variable Speed Operation 66

2.3 Solidity and Loads 68

2.4 Aerofoil Design Development 68

2.5 Sensitivity of Aerodynamic Performance to Planform Shape 73

2.6 Aerofoil Design Specification 74

2.7 Aerofoil Design for Large Rotors 75

References 77

3 Rotor Structural Interactions 79

3.1 Blade Design in General 79

3.2 Basics of Blade Structure 80

3.3 Simplified Cap Spar Analyses 82

3.3.1 Design for Minimum Mass with Prescribed Deflection 83

3.3.2 Design for Fatigue Strength: No Deflection Limits 83

3.4 The Effective t/c Ratio of Aerofoil Sections 84

3.5 Blade Design Studies: Example of a Parametric Analysis 85

3.6 Industrial Blade Technology 91

3.6.1 Design 91

3.6.2 Manufacturing 92

3.6.3 Design Development 94

References 94

4 Upscaling of Wind Turbine Systems 97

4.1 Introduction: Size and Size Limits 97

4.2 The 'Square-Cube' Law 100

4.3 Scaling Fundamentals 100

4.4 Similarity Rules for Wind Turbine Systems 102

4.4.1 Tip Speed 102

4.4.2 Aerodynamic Moment Scaling 103

4.4.3 Bending Section Modulus Scaling 103

4.4.4 Tension Section Scaling 103

4.4.5 Aeroelastic Stability 103

4.4.6 Self-Weight Load Scaling 103 ...