Unsteady oscillation of a deformable airfoil section in incompressible flow

Grishanina, T. V.; Shklyarchuk, F. N.

doi:10.3103/s1068799809020019

Cited by 7 publications

(3 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Aerodynamic characteristics and the potential performance enhancement of deformable airfoils have been studied (e.g., [10][11][12][13]) in the literature. These studies usually consider the impact of the airfoil's flexibility on the aerodynamic loads on the segment.…”

Section: Introductionmentioning

confidence: 99%

Estimation of morphing airfoil shape and aerodynamic load using artificial hair sensors

Butler

Magar

et al. 2016

SPIE Proceedings

View full text Add to dashboard Cite

An active area of research in adaptive structures focuses on the use of continuous wing shape changing methods as a means of replacing conventional discrete control surfaces and increasing aerodynamic efficiency. Although many shapechanging methods have been used since the beginning of heavier-than-air flight, the concept of performing camber actuation on a fully-deformable airfoil has not been widely applied. A fundamental problem of applying this concept to real-world scenarios is the fact that camber actuation is a continuous, time-dependent process. Therefore, if camber actuation is to be used in a closed-loop feedback system, one must be able to determine the instantaneous airfoil shape as well as the aerodynamic loads at all times. One approach is to utilize a new type of artificial hair sensors developed at the Air Force Research Laboratory to determine the flow conditions surrounding deformable airfoils. In this work, the hair sensor measurement data will be simulated by using the flow solver XFoil, with the assumption that perfect data with no noise can be collected from the hair sensor measurements. Such measurements will then be used in an artificial neural network based process to approximate the instantaneous airfoil camber shape, lift coefficient, and moment coefficient at a given angle of attack. Various aerodynamic and geometrical properties approximated from the artificial hair sensor and artificial neural network system will be compared with the results of XFoil in order to validate the approximation approach.

show abstract

Section: Introductionmentioning

confidence: 99%

Estimation of morphing airfoil shape and aerodynamic load using artificial hair sensors

Butler

Magar

et al. 2016

SPIE Proceedings

View full text Add to dashboard Cite

show abstract

“…Aerodynamic characteristics and the potential performance enhancement of deformable airfoils have been studied (e.g., [15][16][17][18]) in the literature. These studies usually consider the impact of the airfoil's flexibility on the aerodynamic loads on the segment.…”

Section: Introductionmentioning

confidence: 99%

Modified Strain-Based Geometrically Nonlinear Beam Formulation for Modeling Slender Wings with Deformable Cross-Sections

2014

55th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference

View full text Add to dashboard Cite

A strain-based geometrically-nonlinear beam formulation has previously been developed and applied in analyzing slender wings of very flexible aircraft. This formulation features strains and curvatures of the beam reference line as the independent variables in the solution. In this study, the deformation of beam cross-sections (warping) is allowed in the modeling process. The warping field of the beam is represented by the Ritz approximation functions at each cross-section, as well as their spatial variations along the beam span. This treatment enhances the one-dimensional beam formulation associated with large-scale beam bending/twist curvatures, with the additional elastic degrees of freedom that consider smallscale local deformations of the cross-sections. It has the potential to provide an efficient solution base for preliminary design and time-domain analysis of flexible aircraft with compliant airfoils, as well as the shape and load control of very flexible aircraft with active actuations. Nomenclature B= body reference frame B F , B M = influence matrices for distributed forces and moments b = positions and orientations of B frame, as time integral of β D = constitutive matrix E n = inertia sub-matrix consisting of influence from finite-section modes ψ n F n = inertia sub-matrix consisting of self-influence from finite-section modes ψ n F dist , F pt = distributed and point forces G = global (inertial) reference frame g = gravity acceleration column vector, m/s 2 H hb = matrix consisting of influence from Jacobian J hb and body angular velocities ω B h = width of the strip section, m h = absolute positions and rotations of beam nodes h r = relative positions and rotations of beam nodes J = Jacobian matrix K  , n q K  , n q K  , n n q q K = components of element stiffness matrix k = cross-sectional stiffness matrix L n = gravity sub-matrix consisting of influence from finite-section modes ψ n l = beam/wing span, m M, C, K = discrete mass, damping, and stiffness matrices of whole system M dist , M pt = distributed and point moments N = influence matrix for gravity force N q = numer of finite-section modes p B , θ B = position and orientation of B frame, as time integral of v B and ω B , respectively p w = position of w frame with respect to B frame q n = magnitude of finite-section modes 1 Assistant Professor (suw@eng.ua.edu), Dept. of Aerospace Engineering and Mechanics, Senior Member AIAA. Downloaded by KUNGLIGA TEKNISKA HOGSKOLEN KTH on July 29, 2015 | http://arc.aiaa.org | 2 b R , n q R , R  = rigid-body, camber, and flexible components of generalized load vector r = warping field r = residual warping field s = beam curvilinear coordinate, m t = thickness of the strip section, m U = total strain energy of the beam v B , ω B = linear and angular velocities of B frame, resolved in B frame itself W ext , W int = external and internal virtual work, respectively w = local beam reference frame defined at each node along beam reference line β = body velocities, with translational and angular components, re...

show abstract

“…Aerodynamic characteristics and the potential performance enhancement of deformable airfoils have been studied in the literature (e.g., [8][9][10][11]). These studies usually considered the impact of the airfoil's flexibility on the aerodynamic loads on the airfoil segment.…”

Section: Introductionmentioning

confidence: 99%

Development of an Aeroelastic Formulation for Deformable Airfoils Using Orthogonal Polynomials

2017

AIAA Journal

View full text Add to dashboard Cite

Unsteady oscillation of a deformable airfoil section in incompressible flow

Cited by 7 publications

References 5 publications

Estimation of morphing airfoil shape and aerodynamic load using artificial hair sensors

Estimation of morphing airfoil shape and aerodynamic load using artificial hair sensors

Modified Strain-Based Geometrically Nonlinear Beam Formulation for Modeling Slender Wings with Deformable Cross-Sections

Development of an Aeroelastic Formulation for Deformable Airfoils Using Orthogonal Polynomials

Contact Info

Product

Resources

About