Modeling Helicopter Blade Dynamics Using a Modified Myklestad-Prohl Transfer Matrix Method
Modeling Helicopter Blade Dynamics Using a Modified Myklestad-Prohl Transfer Matrix Method

Author: Juan D. Cuesta

Publisher:

Published: 1994

Total Pages: 65

ISBN-13:

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Rotor Blade vibratory stresses are of utmost importance in helicopter design. A modified Myklestad-Prohl method for rotating beams has been coded to assist in preliminary helicopter rotor blade design. The rotor blade dynamics program is part of the Joint Army/Navy Rotorcraft Analysis and Design (JANRAD) program which was developed to aid in the preliminary design and analysis of helicopter rotor performance, stability and control, and rotor dynamics. JANRAD is an interactive, user friendly program written in MATLAB version 4.0 programming language and has been used extensively in the Naval Postgraduate School's capstone helicopter design course (AA 4306). A sample case is run and results are discussed.

Scientific and Technical Aerospace Reports
Scientific and Technical Aerospace Reports

Author:

Publisher:

Published: 1995

Total Pages: 602

ISBN-13:

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Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.

Masters Theses in the Pure and Applied Sciences
Masters Theses in the Pure and Applied Sciences

Author: Wade H. Shafer

Publisher: Springer Science & Business Media

Published: 2012-12-06

Total Pages: 341

ISBN-13: 1461559693

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Masters Theses in the Pure and Applied Sciences was first conceived, published, and disseminated by the Center for Information and Numerical Data Analysis and Synthesis (CINDAS)* at Purdue University in 1957, starting its coverage of theses with the academic year 1955. Beginning with Volume 13, the printing and dis semination phases of the activity were transferred to University Microfilms/Xerox of Ann Arbor, Michigan, with the thought that such an arrangement would be more beneficial to the academic and general scientific and technical community. After five years of this jOint undertaking we had concluded that it was in the interest of all concerned if the printing and distribution of the volumes were handled by an international publishing house to assure improved service and broader dissemination. Hence, starting with Volume 18, Masters Theses in the Pure and Applied Sciences has been disseminated on a worldwide basis by Plenum Publishing Corporation of New York, and in the same year the coverage was broadened to include Canadian universities. All back issues can also be ordered from Plenum. We have reported in Volume 40 (thesis year 1995) a total of 10,746 thesis titles from 19 Canadian and 144 United States universities. We are sure that this broader base for these titles reported will greatly enhance the value of this impor tant annual reference work. While Volume 40 reports theses submitted in 1995, on occasion, certain uni versities do report theses submitted in previous years but not reported at the time.

Development of a Myklestad's Rotor Blade Dynamic Analysis Code for Application to JANRAD
Development of a Myklestad's Rotor Blade Dynamic Analysis Code for Application to JANRAD

Author: Dogan Ozturk

Publisher:

Published: 2002-09-01

Total Pages: 236

ISBN-13: 9781423507130

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Blade Dynamics Analysis is a major portion of a helicopter design. The success of the design is strictly related to accuracy of the blade dynamic calculations. The natural frequencies and the mode shapes are not only difficult to calculate but also can be a time consuming procedure. The Myklestad Extension Method gives the designer the opportunity of calculating correct values of the natural frequencies and the mode shapes when centrifugal forces are present. This thesis provides a transfer matrix Myklestad analysis programmed in MATLAB and a Graphical User Interface (GUI) tool built in the MATLAB programming language version 6.1, to implement the Myklestad Extension Method. The generated code and the GUI are designed to be a part of Blade Dynamics Module' of Joint Army/Navy Rotorcraft Analysis Design (JANRAD). For comparison, nonrotating and uniform beam data from Young and Felgar and the actual data of H-3 (S-6 1) helicopter blade are used. Results of the comparison show that the accuracy and robustness of the program are very good, which would make this generated code a valuable part of the helicopter designer's toolbox.

Modeling, Control and Coordination of Helicopter Systems
Modeling, Control and Coordination of Helicopter Systems

Author: Beibei Ren

Publisher: Springer Science & Business Media

Published: 2012-02-02

Total Pages: 243

ISBN-13: 1461415632

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Modeling, Control and Coordination of Helicopter Systems provides a comprehensive treatment of helicopter systems, ranging from related nonlinear flight dynamic modeling and stability analysis to advanced control design for single helicopter systems, and also covers issues related to the coordination and formation control of multiple helicopter systems to achieve high performance tasks. Ensuring stability in helicopter flight is a challenging problem for nonlinear control design and development. This book is a valuable reference on modeling, control and coordination of helicopter systems,providing readers with practical solutions for the problems that still plague helicopter system design and implementation. Readers will gain a complete picture of helicopters at the systems level, as well as a better understanding of the technical intricacies involved.

Nonlinear Dynamics in the Modeling of Helicopter Rotor Blade Lead/Lag Motion
Nonlinear Dynamics in the Modeling of Helicopter Rotor Blade Lead/Lag Motion

Author: Robert L. King

Publisher:

Published: 1999-06-01

Total Pages: 176

ISBN-13: 9781423543527

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Until recently, computer simulations of helicopter rotor dynamics have employed equations of motion that have been linearized or simplified. These modified equations of motion did not allow for the evaluation of nonlinear material properties in the rotor since higher order terms in the dynamics had been modified in the simplification process. With recent advances in both computer simulation hardware and symbolic mathematic manipulation software, the full nonlinear equations of motion may be utilized in helicopter rotor simulations. This dissertation reports on the use of the full nonlinear equations of motion in the analysis of rotor blade lead/lag motion and its effect on rotor hub and rigid body fulselage motion. Nonlinear modeling methods are implemented using Maple symbolic mathematic manipulation software and Matlab and Simulink computer simulation environments. Results are compared to the RAH- 66 Comanche Froude scale wind tunnel article and new methodologies evaluated in the search for a damperless rotor system that is free of ground and air resonance mechanical instabilities.

Helicopter Flight Dynamics
Helicopter Flight Dynamics

Author: G. D. Padfield

Publisher: AIAA (American Institute of Aeronautics & Astronautics)

Published: 1996

Total Pages: 552

ISBN-13:

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This volume provides a comprehensive treatment of the theoretical background to the dynamics of helicopter flight, the development of handling criteria, and new flight-test techniques. Flying quality is described from both objective and subjective perspectives, and test results are presented from a variety of different sources.