Author: Gordon J. Leishman
Publisher: Cambridge University Press
ISBN: 9780521858601
Category : Science
Languages : en
Pages : 860
Book Description
Written by an internationally recognized teacher and researcher, this book provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft such as tilt rotors and autogiros. The text begins with a unique technical history of helicopter flight, and then covers basic methods of rotor aerodynamic analysis, and related issues associated with the performance of the helicopter and its aerodynamic design. It goes on to cover more advanced topics in helicopter aerodynamics, including airfoil flows, unsteady aerodynamics, dynamic stall, and rotor wakes, and rotor-airframe aerodynamic interactions, with final chapters on autogiros and advanced methods of helicopter aerodynamic analysis. Extensively illustrated throughout, each chapter includes a set of homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thoroughly revised and updated text on rotating-wing aerodynamics.
Principles of Helicopter Aerodynamics with CD Extra
Author: Gordon J. Leishman
Publisher: Cambridge University Press
ISBN: 9780521858601
Category : Science
Languages : en
Pages : 860
Book Description
Written by an internationally recognized teacher and researcher, this book provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft such as tilt rotors and autogiros. The text begins with a unique technical history of helicopter flight, and then covers basic methods of rotor aerodynamic analysis, and related issues associated with the performance of the helicopter and its aerodynamic design. It goes on to cover more advanced topics in helicopter aerodynamics, including airfoil flows, unsteady aerodynamics, dynamic stall, and rotor wakes, and rotor-airframe aerodynamic interactions, with final chapters on autogiros and advanced methods of helicopter aerodynamic analysis. Extensively illustrated throughout, each chapter includes a set of homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thoroughly revised and updated text on rotating-wing aerodynamics.
Publisher: Cambridge University Press
ISBN: 9780521858601
Category : Science
Languages : en
Pages : 860
Book Description
Written by an internationally recognized teacher and researcher, this book provides a thorough, modern treatment of the aerodynamic principles of helicopters and other rotating-wing vertical lift aircraft such as tilt rotors and autogiros. The text begins with a unique technical history of helicopter flight, and then covers basic methods of rotor aerodynamic analysis, and related issues associated with the performance of the helicopter and its aerodynamic design. It goes on to cover more advanced topics in helicopter aerodynamics, including airfoil flows, unsteady aerodynamics, dynamic stall, and rotor wakes, and rotor-airframe aerodynamic interactions, with final chapters on autogiros and advanced methods of helicopter aerodynamic analysis. Extensively illustrated throughout, each chapter includes a set of homework problems. Advanced undergraduate and graduate students, practising engineers, and researchers will welcome this thoroughly revised and updated text on rotating-wing aerodynamics.
Aeroelastic Model Helicopter Rotor Testing in the Langley TDT
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages : 22
Book Description
Performance Data from a Wind-tunnel Test of Two Main-rotor Blade Designs for a Utility-class Helicopter
Author: Jeffrey D. Singleton
Publisher: DIANE Publishing
ISBN: 1428915508
Category : Rotors (Helicopters)
Languages : en
Pages : 86
Book Description
Publisher: DIANE Publishing
ISBN: 1428915508
Category : Rotors (Helicopters)
Languages : en
Pages : 86
Book Description
Wind Tunnel Evaluation of a Model Helicopter Main-Rotor Blade With Slotted Airfoils at the Tip
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 134
Book Description
Data for rotors using unconventional airfoils are of interest to permit an evaluation of this technology's capability to meet the U.S. Army's need for increased helicopter mission effectiveness and improved safety and survivability. Thus, an experimental investigation was conducted in the Langley Transonic Dynamics Tunnel (TDT) to evaluate the effect of using slotted airfoils in the rotor blade tip region (85 to 100 percent radius) on rotor aerodynamic performance and loads. Four rotor configurations were tested in forward flight at advance ratios from 0.15 to 0.45 and in hover in-ground effect. The hover tip Mach number was 0.627, which is representative of a design point of 4000-ft geometric altitude and a temperature of 95 degrees F. The baseline rotor configuration had a conventional single element airfoil in the tip region. A second rotor configuration had a forward-slotted airfoil with a -6 degrees slat, a third configuration had a forward-slotted airfoil with a -10 degrees slat, and a fourth configuration had an aft-slotted airfoil with a 3 degrees flap (trailing edge down). The results of this investigation indicate that the -6 degrees slat configuration offers some performance and loads benefits over the other three configurations.
Publisher:
ISBN:
Category :
Languages : en
Pages : 134
Book Description
Data for rotors using unconventional airfoils are of interest to permit an evaluation of this technology's capability to meet the U.S. Army's need for increased helicopter mission effectiveness and improved safety and survivability. Thus, an experimental investigation was conducted in the Langley Transonic Dynamics Tunnel (TDT) to evaluate the effect of using slotted airfoils in the rotor blade tip region (85 to 100 percent radius) on rotor aerodynamic performance and loads. Four rotor configurations were tested in forward flight at advance ratios from 0.15 to 0.45 and in hover in-ground effect. The hover tip Mach number was 0.627, which is representative of a design point of 4000-ft geometric altitude and a temperature of 95 degrees F. The baseline rotor configuration had a conventional single element airfoil in the tip region. A second rotor configuration had a forward-slotted airfoil with a -6 degrees slat, a third configuration had a forward-slotted airfoil with a -10 degrees slat, and a fourth configuration had an aft-slotted airfoil with a 3 degrees flap (trailing edge down). The results of this investigation indicate that the -6 degrees slat configuration offers some performance and loads benefits over the other three configurations.
A Historical Overview of Aeroelasticity Branch and Transonic Dynamics Tunnel Contributions to Rotorcraft Technology and Development
Author:
Publisher: DIANE Publishing
ISBN: 1428995803
Category :
Languages : en
Pages : 115
Book Description
Publisher: DIANE Publishing
ISBN: 1428995803
Category :
Languages : en
Pages : 115
Book Description
Wind-tunnel Evaluation of an Advanced Main-rotor Blade Design for a Utility-class Helicopter
Author:
Publisher:
ISBN:
Category : Rotors (Helicopters)
Languages : en
Pages : 44
Book Description
Publisher:
ISBN:
Category : Rotors (Helicopters)
Languages : en
Pages : 44
Book Description
Scientific and Technical Aerospace Reports
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 994
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 994
Book Description
Wind-tunnel Evaluation of an Advanced Main-rotor Blade Design for a Utility-class Helicopter
Author: William T. Yeager (Jr.)
Publisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
An investigation was conducted in the Langley Transonic Dynamics Tunnel to evaluate differences between an existing utility-class main-rotor blade and an advanced-design main-rotor blade. The two rotor-blade designs were compared with regard to rotor performance, oscillatory pitch-link loads, and 4-per-rev vertical fixed-system loads. Tests were conducted in hover and over a range of simulated full-scale gross weights and density altitude conditions at advance ratios from 0.15 to 0.40. Results indicate that the advanced-blade design offers performance improvements over the baseline blade in both hover and forward flight. Pitch-link oscillatory loads for the baseline rotor were more sensitive to the test condition than those of the advanced blade was larger than that produced by the baseline blade at all test conditions.
Publisher:
ISBN:
Category :
Languages : en
Pages : 44
Book Description
An investigation was conducted in the Langley Transonic Dynamics Tunnel to evaluate differences between an existing utility-class main-rotor blade and an advanced-design main-rotor blade. The two rotor-blade designs were compared with regard to rotor performance, oscillatory pitch-link loads, and 4-per-rev vertical fixed-system loads. Tests were conducted in hover and over a range of simulated full-scale gross weights and density altitude conditions at advance ratios from 0.15 to 0.40. Results indicate that the advanced-blade design offers performance improvements over the baseline blade in both hover and forward flight. Pitch-link oscillatory loads for the baseline rotor were more sensitive to the test condition than those of the advanced blade was larger than that produced by the baseline blade at all test conditions.
Smart Helicopter Rotors
Author: Ranjan Ganguli
Publisher: Springer
ISBN: 3319247689
Category : Technology & Engineering
Languages : en
Pages : 264
Book Description
Exploiting the properties of piezoelectric materials to minimize vibration in rotor-blade actuators, this book demonstrates the potential of smart helicopter rotors to achieve the smoothness of ride associated with jet-engined, fixed-wing aircraft. Vibration control is effected using the concepts of trailing-edge flaps and active-twist. The authors’ optimization-based approach shows the advantage of multiple trailing-edge flaps and algorithms for full-authority control of dual trailing-edge-flap actuators are presented. Hysteresis nonlinearity in piezoelectric stack actuators is highlighted and compensated by use of another algorithm. The idea of response surfaces provides for optimal placement of trailing-edge flaps. The concept of active twist involves the employment of piezoelectrically induced shear actuation in rotating beams. Shear is then demonstrated for a thin-walled aerofoil-section rotor blade under feedback-control vibration minimization. Active twist is shown to be significant in reducing vibration caused by dynamic stall. The exposition of ideas, materials and algorithms in this monograph is supported by extensive reporting of results from numerical simulations of smart helicopter rotors. This monograph will be a valuable source of reference for researchers and engineers with backgrounds in aerospace, mechanical and electrical engineering interested in smart materials and vibration control. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series offers an opportunity for researchers to present an extended exposition of new work in all aspects of industrial control.
Publisher: Springer
ISBN: 3319247689
Category : Technology & Engineering
Languages : en
Pages : 264
Book Description
Exploiting the properties of piezoelectric materials to minimize vibration in rotor-blade actuators, this book demonstrates the potential of smart helicopter rotors to achieve the smoothness of ride associated with jet-engined, fixed-wing aircraft. Vibration control is effected using the concepts of trailing-edge flaps and active-twist. The authors’ optimization-based approach shows the advantage of multiple trailing-edge flaps and algorithms for full-authority control of dual trailing-edge-flap actuators are presented. Hysteresis nonlinearity in piezoelectric stack actuators is highlighted and compensated by use of another algorithm. The idea of response surfaces provides for optimal placement of trailing-edge flaps. The concept of active twist involves the employment of piezoelectrically induced shear actuation in rotating beams. Shear is then demonstrated for a thin-walled aerofoil-section rotor blade under feedback-control vibration minimization. Active twist is shown to be significant in reducing vibration caused by dynamic stall. The exposition of ideas, materials and algorithms in this monograph is supported by extensive reporting of results from numerical simulations of smart helicopter rotors. This monograph will be a valuable source of reference for researchers and engineers with backgrounds in aerospace, mechanical and electrical engineering interested in smart materials and vibration control. Advances in Industrial Control aims to report and encourage the transfer of technology in control engineering. The rapid development of control technology has an impact on all areas of the control discipline. The series offers an opportunity for researchers to present an extended exposition of new work in all aspects of industrial control.
NASA Technical Memorandum
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 464
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 464
Book Description