Author: Gary M. Graham
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Semi-empirical Indicial Response Model for a 65 Degrees Delta Wing Oscillating in Roll
Author: Gary M. Graham
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Select Means for Determining Unsteady Aerodynamic Response Characteristics from Static Data
Author: Gregory A. Addington
Publisher:
ISBN:
Category : Aerodynamic load
Languages : en
Pages : 38
Book Description
Recent analysis has shown that nearly every high-performance tactical aircraft in the inventory of American and allied air forces has experienced some sort of unexpected controlled-flight departure in the early stages of flight testing. Most, if not all, of these in-flight departures had characteristics which lead to the conclusion that they were the result of critical state encounters. Critical states are discrete flight mechanical state vector values where the aerodynamic response loses its analytic dependence on one or more of the variables in that state vector. Critical states manifest themselves as discontinuities in either magnitude or slope in static force and moment data, and as dynamic responses which may be nonlinear with respect to either geometric parameters and/or time. This report presents two analysis procedures which have shown promise in the detection of critical states. First, spectral analysis of data ensembles acquired during wind tunnel tests of two 65 degree delta wings has shown that changes in these spectra signal the presence of some critical states. Further, the nature of these spectra have in some instances provided insight into the nature of the dynamic response. The second analysis procedure involves comparing the static experimental data to a simple potential-flow-based numerical model. It was found that when the experimental dataset diverged from the numerical simulation, critical states were present. Both of these analysis procedures required no additional data to be acquired and minimal analytical effort. Therefore, they provide a cost-effective means for adverting the effects of critical states during early air vehicle test-and-evaluation programs.
Publisher:
ISBN:
Category : Aerodynamic load
Languages : en
Pages : 38
Book Description
Recent analysis has shown that nearly every high-performance tactical aircraft in the inventory of American and allied air forces has experienced some sort of unexpected controlled-flight departure in the early stages of flight testing. Most, if not all, of these in-flight departures had characteristics which lead to the conclusion that they were the result of critical state encounters. Critical states are discrete flight mechanical state vector values where the aerodynamic response loses its analytic dependence on one or more of the variables in that state vector. Critical states manifest themselves as discontinuities in either magnitude or slope in static force and moment data, and as dynamic responses which may be nonlinear with respect to either geometric parameters and/or time. This report presents two analysis procedures which have shown promise in the detection of critical states. First, spectral analysis of data ensembles acquired during wind tunnel tests of two 65 degree delta wings has shown that changes in these spectra signal the presence of some critical states. Further, the nature of these spectra have in some instances provided insight into the nature of the dynamic response. The second analysis procedure involves comparing the static experimental data to a simple potential-flow-based numerical model. It was found that when the experimental dataset diverged from the numerical simulation, critical states were present. Both of these analysis procedures required no additional data to be acquired and minimal analytical effort. Therefore, they provide a cost-effective means for adverting the effects of critical states during early air vehicle test-and-evaluation programs.
35th Aerospace Sciences Meeting & Exhibit
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 544
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 544
Book Description
International Aerospace Abstracts
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 940
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 940
Book Description
Non-linear and Unsteady Aerodynamic Responses of a Rolling 65-degree Delta Wing
Author: Alexander H. Hsia
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Publisher:
ISBN:
Category :
Languages : en
Pages :
Book Description
Journal of Aircraft
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 756
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 756
Book Description
NASA SP.
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 512
Book Description
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 512
Book Description
Aeronautical Engineering
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 216
Book Description
A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 216
Book Description
A selection of annotated references to unclassified reports and journal articles that were introduced into the NASA scientific and technical information system and announced in Scientific and technical aerospace reports (STAR) and International aerospace abstracts (IAA).
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.
Introduction to Nonlinear Aeroelasticity
Author: Grigorios Dimitriadis
Publisher: John Wiley & Sons
ISBN: 1118756460
Category : Technology & Engineering
Languages : en
Pages : 944
Book Description
Introduction to Nonlinear Aeroelasticity Introduces the latest developments and technologies in the area of nonlinear aeroelasticity Nonlinear aeroelasticity has become an increasingly popular research area in recent years. There have been many driving forces behind this development, increasingly flexible structures, nonlinear control laws, materials with nonlinear characteristics and so on. Introduction to Nonlinear Aeroelasticity covers the theoretical basics in nonlinear aeroelasticity and applies the theory to practical problems. As nonlinear aeroelasticity is a combined topic, necessitating expertise from different areas, the book introduces methodologies from a variety of disciplines such as nonlinear dynamics, bifurcation analysis, unsteady aerodynamics, non-smooth systems and others. The emphasis throughout is on the practical application of the theories and methods, so as to enable the reader to apply their newly acquired knowledge Key features: Covers the major topics in nonlinear aeroelasticity, from the galloping of cables to supersonic panel flutter Discusses nonlinear dynamics, bifurcation analysis, numerical continuation, unsteady aerodynamics and non-smooth systems Considers the practical application of the theories and methods Covers nonlinear dynamics, bifurcation analysis and numerical methods Accompanied by a website hosting Matlab code Introduction to Nonlinear Aeroelasticity is a comprehensive reference for researchers and workers in industry and is also a useful introduction to the subject for graduate and undergraduate students across engineering disciplines.
Publisher: John Wiley & Sons
ISBN: 1118756460
Category : Technology & Engineering
Languages : en
Pages : 944
Book Description
Introduction to Nonlinear Aeroelasticity Introduces the latest developments and technologies in the area of nonlinear aeroelasticity Nonlinear aeroelasticity has become an increasingly popular research area in recent years. There have been many driving forces behind this development, increasingly flexible structures, nonlinear control laws, materials with nonlinear characteristics and so on. Introduction to Nonlinear Aeroelasticity covers the theoretical basics in nonlinear aeroelasticity and applies the theory to practical problems. As nonlinear aeroelasticity is a combined topic, necessitating expertise from different areas, the book introduces methodologies from a variety of disciplines such as nonlinear dynamics, bifurcation analysis, unsteady aerodynamics, non-smooth systems and others. The emphasis throughout is on the practical application of the theories and methods, so as to enable the reader to apply their newly acquired knowledge Key features: Covers the major topics in nonlinear aeroelasticity, from the galloping of cables to supersonic panel flutter Discusses nonlinear dynamics, bifurcation analysis, numerical continuation, unsteady aerodynamics and non-smooth systems Considers the practical application of the theories and methods Covers nonlinear dynamics, bifurcation analysis and numerical methods Accompanied by a website hosting Matlab code Introduction to Nonlinear Aeroelasticity is a comprehensive reference for researchers and workers in industry and is also a useful introduction to the subject for graduate and undergraduate students across engineering disciplines.