A5077546855- Aeroelasticity and Vibration Control
- Composite Structure Analysis and Optimization
- Structural Analysis and Optimization
- Vibration and Dynamic Analysis
- Vibration Control and Rheological Fluids
- Fluid Dynamics and Vibration Analysis
- Biomimetic flight and propulsion mechanisms
- Aerodynamics and Fluid Dynamics Research
- Computational Fluid Dynamics and Aerodynamics
- Dynamics and Control of Mechanical Systems
- Advanced Aircraft Design and Technologies
- Bladed Disk Vibration Dynamics
- Cellular and Composite Structures
- Mechanical Engineering and Vibrations Research
- Aerospace Engineering and Energy Systems
- Probabilistic and Robust Engineering Design
- Aerospace Engineering and Control Systems
- Structural Engineering and Vibration Analysis
- Turbomachinery Performance and Optimization
- Aerospace and Aviation Technology
- Carbon Nanotubes in Composites
- Plasma and Flow Control in Aerodynamics
- Magnetic Bearings and Levitation Dynamics
- Elasticity and Material Modeling
- Soil Mechanics and Vehicle Dynamics
University of Nottingham
2021-2024
University of Huddersfield
2020-2022
Swansea University
1970-2020
Amirkabir University of Technology
2015-2017
K.N.Toosi University of Technology
2011-2016
There is an emerging trend in the morphing aircraft research where two or more degrees of freedom are used on a wing which leads to concept polymorphing. The skin must be flexible direction but stiff other directions withstand aerodynamic loads and maintain airfoil shape. Polymorphing changes loadings profile (from uniaxial biaxial) increases complexity designing suitable skins. Furthermore, elastomeric materials wings usually prestretched prevent wrinkling increase their out-of-plane...
In this paper, the potential effectiveness of a nonlinear energy sink (NES) to absorb from wing that is vibrating as result flying in gusty environment investigated. The structural dynamics simulated using rigid airfoil mounted on two linear/nonlinear springs represent bending and torsional stiffness wing. subjected combination gust aerodynamic loads. unsteady lift moment are modelled Wagner's theory. Furthermore, loads obtained by assuming different profiles, e.g. sharp-edged 1-cosine...
In recent years, the development of lighter and more efficient transport aircraft has led to an increased focus on gust load alleviation. A strategy is based use folding wingtip devices that increase aspect ratio therefore improve performance. Moreover, numerical studies have suggested such a solution may incorporate spring in order provide additional alleviation ability flight. It been shown mass, stiffness connection hinge orientation are key parameters avoid flutter achieve during gusts....
This paper presents the development of a novel polymorphing wing capable Active Span morphing And Passive Pitching (ASAPP) for small UAVs. The span an ASAPP can be actively extended by up to 25% enhance aerodynamic efficiency, whilst its pitch near wingtip passively adjusted alleviate gust loads. To integrate these two mechanisms into one single design, each side is split segments (e.g., inboard and outboard segments). segment used extension passive pitch. consists main spar that translate...
Limit cycle oscillations (LCOs) as well nonlinear aeroelastic analysis of a 3-DOF airfoil motion with cubic restoring moments in the pitch degree freedom are investigated. Aeroelastic equations an control surface incompressible potential flow presented time domain. The harmonic balance (HB) method is utilized to calculate LCO frequency and amplitude for airfoil. Also semi-analytical has revealed presence stable unstable limit cycles, along stability reversal neighborhood Hopf bifurcation....
In this paper, a new concept for morphing composite blades is proposed, and how changes the twist distribution of blade explained. A change in obtained by adding mass to that produces an extra centrifugal force. This force then may produce moment can via extension–twist or bend–twist coupling lamination. These types couplings are present antisymmetrically symmetrically laminated beams, respectively. The dynamics rotating modeled using geometrically exact fully intrinsic beam equations....
In this article, the exact free vibration of porous functionally graded rotating blades is investigated. The nonlinear 3D dynamics blade simulated using geometrically fully intrinsic beam equations, and corresponding cross-sectional properties FG are developed. material through thickness a power law distribution. Furthermore, it assumed that due to manufacturing process, level porosity exists in which turn can affect blade. Two models resembling even uneven distributions considered. First,...
This work develops a morphing concept that utilises metamaterial as the passive device for helicopter blades. The metamaterials are created with bend–twist coupling, which enable blade twist under prescribed bending loads. Finite element analysis (FEA) is performed to investigate influence of unit cell configurations on coupling properties metamaterials. numerical models then validated experimentally through set tests conducted additively manufactured prototypes. Finally, model used design...
In this paper, the aeroelastic stability of a hingeless rotor blade in hover is investigated. The modeled using geometrically exact, fully intrinsic beam equations, whereas aerodynamic loads applied on are simulated based quasi-steady Greenberg theory. Using generalized differential quadrature method, resultant coupled equations discretized and solved, eigenvalues linearized system determined. By inspecting eigenvalues, examined for variations different parameters. obtained results validated...
This paper presents a parametric study on the aeroelasticity of cantilever wings equipped with Flared Hinge Folding Wingtips (FHFWTs). The finite element method is utilized to develop computational, low-fidelity aeroelastic model. wing structure modelled using Euler–Bernoulli beam elements, and unsteady Theodorsen’s aerodynamic strip Theory used for load predictions. PK estimate boundaries. model validated three rectangular, whose properties are available in literature. Then, effect folding...
View Video Presentation: https://doi.org/10.2514/6.2021-0621.vid This paper presents the development of a novel multi-objective polymorphing wing capable Active Span morphing And Passive Pitching (ASAPP) for small UAVs. The wingspan can be actively extended by up to 25% enhance aerodynamic efficiency whilst passive pitch is utilized alleviate gust and maneuver loads at off-design conditions shift lift distribution during 1-g flight. To integrate two degrees freedom into single design, each...
In this paper, the effect of distributed electric propulsion on aeroelastic stability an aircraft wing was investigated. All propulsors, which are different properties, attached to in positions. The structural dynamics modelled by using geometrically exact beam equations, while aerodynamic loads were simulated unsteady theory. propulsors a concentrated mass wing, and motor’s thrust angular momentum taken into account. each propulsor as follower force acting exactly at centre gravity...
In this paper, the effects of initial curvature and lattice core shape on bending vibration sandwich beams are investigated. The three-dimensional (3D) beam is simulated by combining a two-dimensional (2D) cross-sectional analysis with one-dimensional (1D) nonlinear analysis. composed two identical isotropic faces covering core. Four different structures used to take into account effect unit cell dynamic properties beam. governing equations Discretized using time-space scheme. Numerical...