A Hybrid Morphing Trailing Edge Designed for Camber Change of the Control Surface

This paper presents an investigation into the modeling and analysis of an innovative actuation system for a wing with a seamless flexible trailing edge control surface. Research was started with the study of aerodynamic behavior and advantage of the wing in smooth variable chamber shape under control. Based on the concept and design, an experimental wing section integrated with the actuation mechanism was built and tested. The main effort was then made to the modeling of the internal actuation system for the purpose of obtaining the physical properties and accurate modeling of the whole wing structural system. To validate and update the numerical model of the system, vibration test of the actuation system including the mechanism and actuator was carried out. Some key parameters such as the stiffness of the actuation system were identified from vibration test data. The investigation demonstrated a practical approach to quantify some key parameters and update the numerical model of an actuation system.

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Modelling and Sensitivity Analysis of a Variable Geometry Trailing Edge Control Surface

44th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference ◽

10.2514/6.2003-1807 ◽

2003 ◽

Cited By ~ 3

Author(s):

Edwin Forster ◽

Brian Sanders ◽

Frank Eastep

Keyword(s):

Sensitivity Analysis ◽

Control Surface ◽

Variable Geometry ◽

Trailing Edge

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Improved aerostructural performance via aeroservoelastic tailoring of a composite wing

The Aeronautical Journal ◽

10.1017/aer.2018.66 ◽

2018 ◽

Vol 122 (1255) ◽

pp. 1442-1474 ◽

Cited By ~ 2

Author(s):

Eduardo P. Krupa ◽

Jonathan E. Cooper ◽

Alberto Pirrera ◽

Raj Nangia

Keyword(s):

Control Surface ◽

Aerodynamic Load ◽

Trailing Edge ◽

Aeroelastic Tailoring ◽

Fuel Burn ◽

Shape Adaptation ◽

Trade Offs ◽

Trailing Edge Flaps ◽

Gradient Based ◽

Composite Wing

ABSTRACTThis paper investigates the synergies and trade-offs between passive aeroelastic tailoring and adaptive aeroelastic deformation of a transport composite wing for fuel burn minimisation. This goal is achieved by optimising thickness and stiffness distributions of constitutive laminates, jig-twist shape and distributed control surface deflections through different segments of a nominal “cruise-climb” mission. Enhanced aerostructural efficiency is sought both passively and adaptively as a means of aerodynamic load redistribution, which, in turn, is used for manoeuvre load relief and minimum drag dissipation. Passive shape adaptation is obtained by embedding shear-extension and bend-twist couplings in the laminated wing skins. Adaptive camber changes are provided via full-span trailing-edge flaps. Optimised design solutions are found using a bi-level approach that integrates gradient-based and particle swarm optimisations in order to tailor structural properties at rib-bay level and retrieve blended stacking sequences. Performance benefits from the combination of passive aeroelastic tailoring with adaptive control devices are benchmarked in terms of fuel burn and a payload-range efficiency. It is shown that the aeroservoelastically tailored composite design allows for significant weight and fuel burn improvements when compared to a similar all-metallic wing. Additionally, the trailing-edge flap augmentation can extend the aircraft performance envelope and improve the overall cruise span efficiency to nearly optimal lift distributions.

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Multi-Material Printed Trailing Edge Control Surface for an Aeroservoelastic Wind Tunnel Model

2018 Multidisciplinary Analysis and Optimization Conference ◽

10.2514/6.2018-2930 ◽

2018 ◽

Cited By ~ 4

Author(s):

Alexander M. Pankonien ◽

Ryan Durscher ◽

Nitin D. Bhagat ◽

Gregory Reich

Keyword(s):

Wind Tunnel ◽

Control Surface ◽

Trailing Edge ◽

Wind Tunnel Model ◽

Tunnel Model

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Structural and acoustic noise produced by turbulent flow over an elastic trailing edge

Proceedings of the Royal Society of London. Series A: Mathematical and Physical Sciences ◽

10.1098/rspa.1993.0120 ◽

1993 ◽

Vol 442 (1916) ◽

pp. 533-554 ◽

Cited By ~ 27

Keyword(s):

Turbulent Flow ◽

Elastic Plate ◽

Acoustic Noise ◽

Acoustic Radiation ◽

Steel Plates ◽

Control Surface ◽

Secondary Source ◽

Thin Elastic Plate ◽

Mean Flow ◽

Trailing Edge

An analysis is made of the sound and vibration produced by turbulent flow at low Mach number over the trailing edge of an elastic plate. The trailing edges of airfoils and other flow control surfaces are known to be important sources of high frequency sound. When the surface is compliant the turbulent edge-flow also excites structural modes of vibration. In conditions of heavy fluid loading, which typically occurs in underwater applications, the energy imparted to the structural motions can be large, and the subsequent scattering of ‘surface waves’ at mechanical discontinuities is frequently an important secondary source of sound. In this paper general formulae are developed for the structural and acoustic edge-noise when the control surface is modelled by a semi-infinite, thin elastic plate which can support bending waves. Numerical results are given for steel plates in air and in water. In the latter case it is shown that, when the frequency is smaller than the coincidence frequency the bending wave power exceeds the total sound power generated at the edge by 20–40 dB, independently of the mean flow velocity, so that sound generated by secondary scattering may then be the dominant source of acoustic radiation.

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Characterization of typical aeroelastic sections under combined structural concentrated nonlinearities

Journal of Vibration and Control ◽

10.1177/10775463211000161 ◽

2021 ◽

pp. 107754632110001

Author(s):

José Augusto I da Silva ◽

Flávio D Marques

Keyword(s):

Time Integration ◽

Unsteady Aerodynamics ◽

Nonlinear Effects ◽

Free Play ◽

Control Surface ◽

Trailing Edge ◽

Aeroelastic System ◽

Practical Applications ◽

Structural Nonlinearities ◽

The Stability

Structural nonlinearities are usually present in aeroelastic systems. The analysis of this system commonly comprises a study involving only one type of nonlinearity, influencing a particular motion of the airfoil. However, practical applications of aeroelastic systems can be affected by different types of structural nonlinearities. It becomes essential to study the stability of the aeroelastic system under these conditions to assess more real operational flight procedures. In this context, this article presents an investigation of a typical aeroelastic section response with trailing edge control surface subjected to combinations of concentrated structural nonlinearities. Different nonlinear scenarios involving cubic hardening stiffness in pitching and free play, free play with preload, and slip dry friction in the trailing edge control surface motion are analyzed. The mathematical model is based on linear unsteady aerodynamics coupled to a three-dof typical aeroelastic section. Hopf bifurcations diagrams are obtained from direct time integration of the equation of motion. The post-flutter limit cycle oscillations are investigated, revealing supercritical and subcritical bifurcations. A complete parametric study of the nonlinear parameters is carried out, thereby allowing a sensitivity analysis of each nonlinear scenario. The results show that aeroelastic tailoring considering the mild post-flutter behavior can be achieved through an appropriate choice of combined nonlinear effects. Moreover, combined nonlinearities can mitigate the undesired subcritical aeroelastic responses caused by free play.

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Measurements of Bluff Body Wake Flow Around a Conformable Flow Control Surface

Noise Control and Acoustics ◽

10.1115/imece2003-55376 ◽

2003 ◽

Author(s):

David A. Ericson ◽

Michael Jonson ◽

Gary Koopmann

Keyword(s):

Flow Control ◽

Vortex Shedding ◽

Flow Separation ◽

Bluff Body ◽

The Body ◽

Control Surface ◽

Periodic Flow ◽

Two Dimensional ◽

Trailing Edge ◽

Shedding Frequency

The vortex street is a unique type of unsteady flow separation seen commonly in flow over a bluff body with a characteristic periodic wake. A consequence of the periodic flow is that the drag and lift forces acting on the body also oscillate periodically. When the wake shedding frequency is near a structural frequency, flow induced resonance will occur. The continuing interest in the study of vortex street generation is propelled by the ever-present nature of these flows in a variety of applications including aerodynamics, hydrodynamics and underwater acoustics. Recent advances in material science and the development of high power density actuators have led to the study of adaptive structure technology wherein the vorticity of periodic flows can be actively controlled by changing the ‘bluffness’ or shape of the body. In this paper, the development and experimental testing of a two-dimensional shape-variable flow control surface are discussed in relation to the generation and manipulation of periodic flow separation. Two series of wind tunnel tests were designed to evaluate the potential of the morphing structure that replaced a section of the trailing edge of a symmetric airfoil. The test section successfully demonstrated a smooth transition between three prescribed trailing edge profiles ranging from sharp to blunt. Unsteady pressure spectra were measured near the trailing edge for three different shape profiles over a range of speeds between 50 and 110 ft/s. The measured pressure spectra amplitudes were compared to previously-published surface pressure spectra of a similar, two-dimensional, blunt edge foil. A second set of tests was performed to measure the resulting flow field in the direction transverse to the flow and downstream from the airfoil. Velocity measurements were made using a traversing hot-wire probe at three trailing edge configurations and speeds of 50, 70 and 90 ft/s. The corresponding Reynolds number based on wake thickness ranged from 3.9–9.8 × 104. Measured vortex shedding frequencies varied between approximately 50 to 130 Hz at the different trailing edge profiles. This type of change in the vortex shedding frequency can be used to reduce flow-induced vibration and its associated noise generation by avoiding shedding frequencies at operating speeds that coincide with airfoil resonances.

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