2 edition of Passive control of wing/store flutter found in the catalog.
Passive control of wing/store flutter
Wilmer H Reed
1980 by National Aeronautics and Space Administration, Scientific and Technical Information Branch, For sale by the National Technical Information Service] in Washington, D.C, [Springfield, Va .
Written in English
|Statement||Wilmer H. Reed III, F.W. Cazier, Jr., and Jerome T. Foughner, Jr|
|Series||NASA technical memorandum -- 81865|
|Contributions||Cazier, F. W, Foughner, Jerome T, United States. National Aeronautics and Space Administration. Scientific and Technical Information Branch, Langley Research Center (U.S.)|
|The Physical Object|
|Pagination||16 p. :|
|Number of Pages||16|
A multi-category children's entertainment company since , Spin Master has been designing, developing, manufacturing and marketing consumer products for children around the world and is recognized as a global growth leader within the toy industry. It takes up all the interior space inside the nose. I have two CF tubes in the wings about 1/4 chord but they don't reach the nose. There is a CF tube just behind the CG across the center, connecting to the wing spars. /-\ I stripped the coating since it was a bit loose, and the covering flapping may have been contributing to the wing flutter. BRITISH RACE PLANE DESTROYED IN TEST; Crash Caused by Wing Flutter Eliminates 'Mystery Ship' in Today's Schneider Cup Contest. PILOT, ILL, RESCUED UNHURT Second Craft, .
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Passive control of wing/store flutter. Washington, D.C.: National Aeronautics and Space Administration, Scientific and Technical Information Branch ; [Springfield, Va.: For sale by the National Technical Information Service], (OCoLC) Material Type: Government publication, National government publication: Document Type: Book.
The present work describes a method for thin-wing flutter control using an array of small, flexible, rectangular polymer fins attached near the leading edge on the upper surface of a wing to manipulate unsteady flow structures.
The dynamic deformation of a rectangular flat-plate wing along with the motions of the fins relative to the wing’s surface are measured using a high-speed Author: Nicholas L. Pohl. Results are presented for a passive flutter suppression approach known as the decoupler pylon.
The decoupler pylon dynamically isolates the wing from store pitch inertia effects by means of soft spring/damper elements assisted by a low frequency feedback control system which minimizes static pitch deflections of the store because of maneuvers and changing flight conditions.
Flutter phenomena associated with various store loadings on modern fighter aircraft wings are diverse and can severely inhibit performance. Passive means of suppressing flutter can be costly in terms of performance as well. Active flutter suppression is a potential means for overcoming these performance : C.
Harvey. The feasibility of a passive control mechanism against flutter instability during erection of a suspension bridge has been investigated in , whereas.
Flutter suppression of plates using passive constrained viscoelastic layers Mechanical Systems and Signal Processing, Vol. 79 Neurofuzzy-Model-Based Unsteady Aerodynamic Computations Across Varying Freestream ConditionsCited by: Active and Passive Control for Acceleration Reduction of an Aeroelastic Typical Wing Section 28 August | Journal of Vibration and Control, Vol.
24, No. 13 Aircraft Active Flutter Suppression: State of the Art and Technology Maturation NeedsCited by: In principle, the semi-active control method investigated has the merits of less control power required, simpler control strategy and better control effects that may provide an emergency or reserved measure to deal with the flutter encounters.
Investigations on wing/store type flutter File Size: KB. In this paper, both experimental and analytical flutter analyses are conducted for a typical 5-degree of freedon (5DOF) wing section carrying a flexibly mounted unbalanced engine.
The wing flexibility is simulated by two torsional and longitudinal springs at the wing elastic : A. Mirabbashi, A. Mazidi, M. Jalili. GARRICK AND W.H. REED III J. AIRCRAFT engineering. The Passive control of wing/store flutter book response of an airplane to rough air (gusts or turbulence) is an importan t aeroelastic problem requiring separate study nd documentation.
Ashe phenomen a nd concept s have unfolded, aeroelasticity, and flutter in particular, have been the subjects. A complete decentralization of the flutter control is however rarely feasible since ACTIVE FLUTTER SUPPRESSION TECHNIQUES IN AIRCRAFT WINGS 75 often the control surfaces, and possibly some sensors, must be shared with the outer control by: 7.
Foughner, Jerome T.: Passive control of wing/store flutter / (Washington, D.C.: National Aeronautics and Space Administration, Scientific and Technical Information Branch ; [Springfield, Va.: Help with reading books-- Report a bad link-- Suggest a new listing. Passive Morphing of Flying Wing Aircraft - Part I: Z Flutter analysis of a nonlinear airfoil using stochastic approach “Theory of Loss of Lateral Control Due to Wing Twisting,” R&MAeronautical Research Council, October Scanlan, R.
H., and R., Rosenbaum, Introduction to the Study of Aircraft Vibration and Cited by: such as wing, tail units and control surfaces.
Wing Flutter is one of the dynamic aero elastic problems, it mainly occurs at lifting. In order to maintain the airplane stability in high-speed, wings can be designed to minimize the distance between aerodynamic centre and shear centre (on the elastic axis).
The main focus of this thesisFile Size: KB. The wing flutter is a dynamic instability of a flight vehicle associated with the interaction of aerodynamic, elastic, and inertial forces (aeroelastics phenomena).
In this study, just the primary control is investigated. Also, in order to control the two-dimensional wing flutter, the force jet and pulse width pulse frequency (PWPF) are : A.
Ansari, A. Novinzadeh. Flutter can occur on fixed surfaces, such as the wing or the stabilizer, as well as on control surfaces such as the aileron or the elevator for instance.
On the following video, you will see how flutter is affecting the stabilizer of a small airplane. Normal mode and flutter analysis are conducted for a high aspect ratio aft swept flying wing model, and body freedom flutter is found to be the most critical aeroelastic instability for this air vehicle model.
To determine the influence of various kinds of design parameters on BFF characteristics, eight factors are considered in the parametric study, i.e. wing vertical bending stiffness Cited by: 1. Dynamic vibration absorber (DVA), a mass-spring-damper assembly attached to the main system, is an alternative passive flutter control technique.
Compressibility at high subsonic speeds has a significant effect on flutter speed of the wing. The compressibility causes a drop of the flutter speed and flutter frequency as compared to the incompressible flow. In addition, the mechanism of flutter may be Cited by: The position of the centre of gravity (CG).
As a rule of thumb, the further forward (towards the nose) the CG, the more stable the aircraft with respect to pitching. However, far-forward CG positions make the aircraft difficult to control, and in fact the aircraft becomes increasingly nose heavy at lower airspeeds, e.g.
during landing. The. The first practical application of TET concerns passive suppression of aeroelastic instabilities in rigid in-flow wings. We show that the capacity of the essentially nonlinear NES to passively absorb vibration energy from a primary structure in a broadband fashion paves the way for robust partial or complete suppression of limit cycle oscillations (LCOs) developing in in-flow wings.
A device for preventing aircraft wing flutter causes the port and starboard wings of the aircraft to oscillate at different frequencies. In an exemplary embodiment, engine nacelles are suspended from the port and starboard wings by strut assemblies in a manner that the port and starboard engine nacelles have different oscillation frequencies when subjected to a displacing by: Flutter and Limit Cycle Oscillation Suppression Using Linear and Nonlinear Tuned Vibration Absorbers A., Touzé, C., Doaré, O., et al.: Passive control of airfoil flutter using a nonlinear tuned vibration absorber.
In: 11th International Conference on Flow-induced vibrations, FIV Kerschen G., Dimitriadis G. () Flutter and Cited by: 2. technology, flutter prevention is done by using passive control methods (i.e.,) impart enough stiffness to the main wings or dynamic mass balancing.
These two methods are not attractivebecause of the weight penalty, imposed on the structures as it is implemented. Theoretical and experimental investigations of Author: Bruce Ralphin, Rose J. The wing root is fixed to the aircraft fuselage, the wing tip is not fixed and can twist.
The air streaming over the wing creates lift, but also creates a twisting moment. A longish body in a fluid stream wants to position itself perpendicular to the stream, that is why we need empennages. Flutter Modeling and Simulation of Wing Section. Using Bondgraph Technique. This thesis is about the investigation of the flutter modeling of wing section or airfoil using Bondgraph technique.
Flutter is the dynamic instability of a structure exposed to airflow. WhenFile Size: KB. An example was presented for conceptual flutter analysis of outer-wing of a Blended-Wing-Body aircraft. 1 INTRODUCTION During conceptual design of a wing, it is often necessary to obtain initial estimates of the wing or tail flutter boundary, when only the File Size: 95KB.
Opportunities – AFS as a response to flutter problems. If flutter or other dynamic aeroelastic problems show up late in the design process, when solution by revised stiffness / inertia / aerodynamic means becomes too costly / impractical: • Use active control, through the action of control effectors driven by actuators and control laws, toFile Size: KB.
Orbital Research has applied ORICA technology to the problem of controlling aircraft wing flutter, movement that is akin to a shimmy in an automobile.
The effectiveness of the control software has been validated during wind tunnel testing at Langley. Typically, aeroelastic tailoring is associated with the tailoring of a wings lift distribution or to allow for better wing gust response, however aeroelastic tailoring can also be used to manipulate the flutter speed and divergence speed of an aircraft.
One of the simplest examples of this kind of tailoring was explored by Dr. Patil in Thesis projects are currently available on the following topics: nonlinear shock absorbers (theory/experiments), shape memory/piroelectric energy harvesters (theory/experiments), hysteretic absorbers for wing flutter control, hysteretic vibration isolation for buildings, innovative hysteretic bracing systems for buildings.
modern control theory; for the sake of clarity, explicit formulae are derived and numerical results are given for a test-case. The validity of the active-flutter-suppression concept is well recognized. The concept's performances will be discussed in Part II of this paper.
Keywords: aeroelasticity, flutter, active flutter suppression 1. Introduction. Propeller whirl flutter is a special case of flutter involving the aerodynamic and inertial effects of a rotating propeller and the stiffness of the supporting nacelle structure.
Dynamic instability can occur involving pitch and yaw degrees of freedom of the propeller and the engine supports leading to an unstable precession of the propeller. . The flutter analysis of a wing with an external store is presented.
Because of the external store, the concentrated store mass is combined into the governing equations which are obtained using the extended Hamiltons principle.
Dirac function is used to precisely consider the location and properties of the external store. The k method is used to calculate the flutter by: 2. The flutter and divergence aspects are rarely covered in most design books, so there can be enhanced safety.
The method presents a unique representation for the preliminary design phase where the wing skin thickness is a key factor readily found and used for the stiffness and weight calculations.4/5(3). the wing and the flutter boundary 13'8'9. Taking in to account these nonlinearities, an understanding of their potential influence on the character of the flutter can be reached.
This paper restricted to a supersonic/hypersonic cross-sectional wing is intended to address these issues. Boeing engineer Pio Fitzgerald's fascination with the began as a kid and culminated when he cured the wingtip flutter problem in the jumbo jet's latest incarnation.
Flutter definition is - to flap the wings rapidly. How to use flutter in a sentence. The nonlinear characteristics of slender wings have been studied for many years, and the influences of the geometric structural nonlinearity on the postflutter responses of the wing have been received significant attention.
In this paper, the effects of the external store on the nonlinear responses of the slender wing will be by: 2. Genes Color a Butterfly’s Wings. Now Scientists Want to Do It Themselves.
The wings of a painted lady butterfly, left, compared to mutants generated with. It was then that flutter was discovered, the wings had been flapping uncontrollably until the load bared by the wings became too much causing them to snap.
As would be assumed in a multibillion dollar business there is a constant strive to reduce the weight of the aircraft whilst also increasing performance.Search the world's most comprehensive index of full-text books.The X Active Aeroelastic Wing (AAW) development program is a completed American research project that was undertaken jointly by the Air Force Research Laboratory (AFRL), Boeing Phantom Works and NASA's Dryden Flight Research Center, where the technology was flight tested on a modified McDonnell Douglas F/A Aeroelastic Wing Technology is a technology that integrates wing Manufacturer: McDonnell Douglas.