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Quasi-steady aerodynamic and von Karman large deflection plate theory equations of nonlinear oscillations of fluttering plate for single mode subsonic and sonic or coupled mode supersonic oscillations
Bending torsional flutter of uniform swept wing with velocity component aerodynamic strip theory
Quasi-steady aerodynamic and von Karman large deflection plate theory equations of nonlinear oscillations of fluttering plate for single mode subsonic and sonic or coupled mode supersonic oscillations
A new time-domain approach for computing flutter speed is presented. Based on the time-history result of aeroelastic simulation, the unknown unsteady aerodynamics model is estimated using a system identification technique. The full aeroelastic model is generated via coupling the estimated unsteady aerodynamic model with the known linear structure model. The critical dynamic pressure is computed and used in the subsequent simulation until the convergence of the critical dynamic pressure is achieved. The proposed method is applied to a benchmark cantilevered rectangular wing.
This presentation is a conference companion and discusses a new flutter analysis technique using CFD results.
This paper presents a transonic correction method for an oscillating airfoil in pitch and plunge. The proposed method applies correction functions to the Theodorsen’s theory to capture the transonic nonlinear aero- dynamics. These correction functions apply necessary corrections to the amplitudes and the phase angles of the unsteady lift and pitching moment coefficients to account for transonic aerodynamics. The proposed method also postulates a correction for the motion of the aerodynamic center which could be induced by moving shocks. A series of unsteady RANS CFD simulations of the airfoil at the mean aerodynamic chord of the Transonic Truss-Braced Wing aircraft are conducted using FUN3D to provide data to construct these transonic correction functions. The computed responses of the unsteady lift and pitching moment coefficients using these transonic correction functions match the CFD simulation results very well even when the pitching moment coefficient is highly nonlinear. A flutter analysis of an airfoil in pitch and plunge illustrates the potential use of the proposed transonic correction method.
The following repositories are a set of libraries that are needed for applications that are being developed for users of the Accelerator control system. The programming language used is Dart and for the user interface use the Flutter framework. URL for code repositories: - https://github.com/fermi-ad/flutter-controls-core - https://github.com/fermi-ad/flutter-controls-plotting - https://github.com/fermi-ad/flutter-controls-auth - https://github.com/fermi-ad/flutter-gql-acsys - https://github.com/fermi-ad/flutter-gql-faas - https://github.com/fermi-ad/dart-gql-acsys - https://github.com/fermi-ad/dart-explicit-imports - https://github.com/fermi-ad/dart-gql-faas - https://github.com/fermi-ad/design-system
Control trailing-edge thickness and aspect ratio effect on oscillating hinge-moment and flutter characteristics of flap-type controls
Movable tail surface for aircraft control without flutter using X-15 scale model at hypersonic speed
Effect of flutter on digital data is recorded by magnetic tape recorders used with instrumentation systems. Major effect for both FM and direct recording techniques is shown to be a perturbation of the signal time base.
Nonlinear flutter of circular cylindrical shell in supersonic flow
Subsonic and transonic flutter and flow studies of T tail of large multijet cargo airplane
Flutter analysis on buckled supported rectangular panels under supersonic surface flow
Turbulent boundary layer effect on panel flutter
Experimental study, and theoretical analysis on supersonic flutter of corrugation stiffened panels
Engineering estimates for supersonic flutter of curved shell panels
Flutter behavior of plates exposed to supersonic flow with concurrent transverse and plane loadings
Plate and shell flutter emphasizing nonlinear aspects and load effects