Blade Element Rotor Theory
This book presents an extension of the conventional blade element rotor theory to describe the dynamic properties of helicopter rotors. The presented theory focuses on the accurate mathematical determination of the forces and moments by which a rotor affects its rotorcraft at specified flight conditions and control positions. Analyzing the impact of a blade's non-uniform properties, the book covers blade twisting, the non-rectangular planform shape of a blade, and inhomogeneous airfoil along the blade. It discusses inhomogeneous induced airflow around a rotor disc in terms of the blade element rotor theory. This book also considers the impact of flapping hinge offset on the rotor's dynamic properties.
Features
• Focuses on a comprehensive description and accurate determination of the rotor's aerodynamic properties
• Presents precise helicopter rotor properties with inhomogeneous aerodynamic properties of rotor blades
• Considers inhomogeneous distribution of induced flow
• Discusses a mathematical model of a main helicopter rotor for a helicopter flight simulator
This book is intended for graduate students and researchers studying rotor dynamics and helicopter flight dynamics
Author(s): Pylyp Volodin
Publisher: CRC Press
Year: 2022
Language: English
Pages: 185
City: Boca Raton
Cover
Half Title
Title Page
Copyright Page
Contents
Preface
Symbols
Acknowledgment
Chapter 1: Introduction
Chapter 2: General Statements
2.1. Construction and Components
2.2. Coordinate Systems and Orientation Angles
2.3. Swashplate Mechanism
2.4. General Statements of the Blade Element Rotor Theory
2.5. Basic Assumptions and Approximations
2.6. Comparison with the Conventional Theory
Chapter 3: Blade Element Properties
3.1. Blade Element Description
3.2. Absolute Velocity of a Blade Point
3.3. Blade Element Air Velocity
3.4. Attack and Sideslip Angles of a Blade Element
3.5. Aerodynamic Properties of a Blade Element
3.6. Blade Elements as Parts of a Rigid Blade
3.7. Equation of Motion of Blade Element Center of Mass
3.8. Equation of Blade Element Rotation
Chapter 4: Characteristic Measures of Non-uniform Parameters
4.1. Basic Concept
4.2. Blade Characteristic Parameters
4.3. Twisting Characteristic Parameters
4.4. Inflow Ratio Characteristic Parameters
4.5. Characteristic Blade Drag Coefficient
4.6. Measures Associated with Aerodynamic Center Position
4.7. Characteristic Pitching Moment Coefficient
Chapter 5: Analysis of Blade Rotations
5.1. Blade Rotation Equations
5.2. Blade Flapping Motion
5.3. Solution of the Blade Cone Equation System
5.4. Analysis of Blade Cone Parameters
5.5. Blade Pitch Force
5.6. Flapping Hinge Reaction Moment
Chapter 6: Force on the Flapping Hinge
6.1. Flapping Hinge Reaction Force
6.2. Force on the Flapping Hinge
Chapter 7: Total Rotor Force
7.1. General Statements About the Total Rotor Force
7.2. Thrust
7.3. Rotor Longitudinal Force
7.4. Rotor Side Force
Chapter 8: Rotor Moment on the Hub
8.1. General Statements About Rotor Moment
8.2. Lateral and Longitudinal Hub Moments
8.3. Blade Resistance Moment on the Rotor Hub
8.4. Rotor Torque
Chapter 9: Conclusions
9.1. Determination of Rotor System Properties
9.2. Summarizing of Rotor System Properties
9.3. Remarks
References
Index
