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Article
Publication date: 18 January 2013

Shi Rongqi and Song Jianmei

The purpose of this paper is to clarify the dynamic principle of internal structure of a complex morphing wing and control the wing to change configurations rapidly and…

Abstract

Purpose

The purpose of this paper is to clarify the dynamic principle of internal structure of a complex morphing wing and control the wing to change configurations rapidly and smoothly. It includes modeling the dynamics of the morphing wing and designing a rational morphing control system.

Design/methodology/approach

The dynamic model of the morphing wing is developed based on Lagrange method of analytical mechanics. The generalized forces are obtained by virtual work principle. Since the morphing wing is a strongly coupled, over‐actuated and nonlinear system with multi‐input and multi‐output, the control system design includes a control allocator, a dynamic inversion controller and two PID controllers. The control allocator is designed based on pseudo inverse method; the dynamic inversion controller is applied to make the original system decoupled into two independent linear systems by proper nonlinear feedback transformation; two classical PID controllers are adopted for the linearlized systems.

Findings

The validity of the dynamic model and the controller is verified according to the simulation results using ADAMS and Matlab. It suggests that integrating Lagrange equation, pseudo inverse allocation, dynamic inversion control and classical PID method, is an effective way to solve problems of dynamic modeling and control for morphing wings.

Research limitations/implications

The flexibility of the structure, the changes of the aerodynamic load, the mass and the dynamic performances of actuators are not taken into account. Therefore, researchers are encouraged to develop a more realistic morphing wing model.

Practical implications

The paper includes implications for the development of a dynamic model of a complex morphing wing and a rational morphing control system.

Originality/value

The paper fulfils a complete process from multi‐rigid‐body dynamic modeling to control system design for an over‐actuated nonlinear complex morphing wing, which could be a foundation of further researches on morphing wing dynamics and control.

Details

Aircraft Engineering and Aerospace Technology, vol. 85 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 1 July 2021

Zi Kan, Daochun Li, Shiwei Zhao, Jinwu Xiang and Enlai Sha

This paper aims to assess the aeroacoustic and aerodynamic performance of a morphing airfoil with a flexible trailing edge (FTE). The objective is to make a comparison of…

Abstract

Purpose

This paper aims to assess the aeroacoustic and aerodynamic performance of a morphing airfoil with a flexible trailing edge (FTE). The objective is to make a comparison of the aerodynamic noise characteristics between the conventional airfoil with a flap and morphing airfoil and analyse the noise reduction mechanisms of the morphing airfoil.

Design/methodology/approach

The computational fluid dynamic method was used to calculate the aerodynamic coefficients of morphing airfoil and the Ffowcs-Williams and Hawking’s acoustic analogy methods were performed to predict the far-field noise of different airfoils.

Findings

Results show that compared with the conventional airfoil, the morphing airfoil can generate higher lift and lower noise, but a greater drag. Additionally, the noise caused by the one-unit lift of the morphing airfoil is significantly lower than that of the conventional airfoil. For the morphing airfoil, the shedding vortex in the trailing edge was the main noise resource. As the angle of attack (AoA) increases, the overall sound pressure level of the morphing airfoil increases significantly. With the increase of the trailing edge deflection angle, the amplitude and the period of sound pressure of the morning airfoil fluctuation increase.

Practical implications

Presented results could be very useful during designing the morphing airfoil with FTE, which has significant advantages in aerodynamic efficiency and aeroacoustic performance.

Originality/value

This paper presents the aerodynamic and aeroacoustic characteristics of the morphing airfoil. The effect of trailing edge deflection angle and AoA on morphing airfoil was investigated. In the future, using a morphing airfoil instead of a traditional flap can reduce the aircraft`s fuel consumption and noise pollution.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 5
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 8 October 2018

Witold Artur Klimczyk and Zdobyslaw Jan Goraj

The purpose of this paper is to present a method for analysis and optimization of morphing wing. Moreover, a numerical advantage of morphing airfoil wing, typically…

Abstract

Purpose

The purpose of this paper is to present a method for analysis and optimization of morphing wing. Moreover, a numerical advantage of morphing airfoil wing, typically assessed in simplified two-dimensional analysis is found using higher fidelity methods.

Design/methodology/approach

Because of multi-point nature of morphing wing optimization, an approach for optimization by analysis is presented. Starting from naïve parametrization, multi-fidelity aerodynamic data are used to construct response surface model. From the model, many significant information are extracted related to parameters effect on objective; hence, design sensitivity and, ultimately, optimal solution can be found.

Findings

The method was tested on benchmark problem, with some easy-to-predict results. All of them were confirmed, along with additional information on morphing trailing edge wings. It was found that wing with morphing trailing edge has around 10 per cent lower drag for the same lift requirement when compared to conventional design.

Practical implications

It is demonstrated that providing a smooth surface on wing gives substantial improvement in multi-purpose aircrafts. Details on how this is achieved are described. The metodology and results presented in current paper can be used in further development of morphing wing.

Originality/value

Most of literature describing morphing airfoil design, optimization or calculations, performs only 2D analysis. Furthermore, the comparison is often based on low-fidelity aerodynamic models. This paper uses 3D, multi-fidelity aerodynamic models. The results confirm that this approach reveals information unavailable with simplified models.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 9 November 2015

Josh P Davis, Stacie Simmons, Lucy Sulley, Chris Solomon and Stuart Gibson

The purpose of this paper is to describe four experiments evaluating post-production enhancement techniques with facial composites mainly created using the EFIT-V holistic…

Abstract

Purpose

The purpose of this paper is to describe four experiments evaluating post-production enhancement techniques with facial composites mainly created using the EFIT-V holistic system.

Design/methodology/approach

Experiments 1-4 were conducted in two stages. In Stage 1, constructors created between one and four individual composites of unfamiliar targets. These were merged to create morphs. Additionally in Experiment 3, composites were vertically stretched. In Stage 2, participants familiar with the targets named or provided target-similarity ratings to the images.

Findings

In Experiments 1-3, correct naming rates were significantly higher to between-witness 4-morphs, within-witness 4-morphs and vertically stretched composites than to individual composites. In Experiment 4, there was a positive relationship between composite-target similarity ratings and between-witness morph-size (2-, 4-, 8-, 16-morphs).

Practical implications

The likelihood of a facial composite being recognised can be improved by morphing and vertical stretch.

Originality/value

This paper improves knowledge of the theoretical underpinnings of these facial composite post-production enhancement techniques. This should encourage acceptance by the criminal justice system, and lead to better detection outcomes.

Details

Journal of Forensic Practice, vol. 17 no. 4
Type: Research Article
ISSN: 2050-8794

Keywords

Article
Publication date: 4 January 2016

Daochun Li, Shijun Guo, Tariq Osman Aburass, Daqing Yang and Jinwu Xiang

The purpose of this study is to develop an active controller of both leading-edge (LE) and trailing-edge (TE) control surfaces for an unmanned air vehicle (UAV) with a…

Abstract

Purpose

The purpose of this study is to develop an active controller of both leading-edge (LE) and trailing-edge (TE) control surfaces for an unmanned air vehicle (UAV) with a composite morphing wing.

Design/methodology/approach

Instead of conventional hinged control surfaces, both LE and TE seamless control surfaces were integrated with the wing. Based on the longitudinal state space equation, the root locus plot of the morphing wing aircraft, with a stability augmented system, was constructed. Using the pole placement, the feedback gain matrix for an active control was obtained.

Findings

The aerodynamic benefits of a morphing wing section are compared with a wing of a rigid control surface. However, the 3D morphing wing with a large sweptback angle produces a washout negative aeroelastic effect, which causes a significant reduction of the control effectiveness. The results show that the stability augmentation system can significantly improve the longitudinal controllability of an aircraft with a morphing wing.

Practical implications

This study is necessary to analyse the effect of a morphing wing on an UAV and perform a comparison with the rigid model.

Originality/value

The control surfaces assignment plan for trim, pitch and roll control was obtained. An active control algorism for the morphing wing was created to satisfy the required stability and control effectiveness by operating the LE and TE control surfaces according to flight conditions. The aeroelastic effect of control derivatives on the morphing aircraft was considered.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 88 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 11 June 2020

Oguz Kose and Tugrul Oktay

The purpose of this paper is to design a quadrotor with collective morphing using the simultaneous perturbation stochastic approximation (SPSA) optimization algorithm.

Abstract

Purpose

The purpose of this paper is to design a quadrotor with collective morphing using the simultaneous perturbation stochastic approximation (SPSA) optimization algorithm.

Design/methodology/approach

Quadrotor design is made by using Solidworks drawing program and some mathematical performance relations. Modelling and simulation are performed in Matlab/Simulink program by using the state space model approaches with the parameters mostly taken from Solidworks. Proportional integral derivative (PID) approach is used as control technique. Morphing amount and the best PID coefficients are determined by using SPSA algorithm.

Findings

By using SPSA algorithm, the amount of morphing and the best PID coefficients are determined, and the quadrotor longitudinal and lateral flights are made most stable via morphing.

Research limitations/implications

It takes quite a long time to model the quadrotor in Solidworks and Matlab/Simulink with the state space model and using the SPSA algorithm. However, this situation is overcome with the proposed model.

Practical implications

Optimization with SPSA is very useful in determining the amount of morphing and PID coefficients for quadrotors.

Social implications

SPSA optimization method is useful in terms of cost, time and practicality.

Originality/value

It is released to improve performance with morphing, to determine morphing rate with SPSA algorithm and to determine PID coefficients accordingly.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 7
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 2 January 2020

Abderahmane Marouf, Yannick Bmegaptche Tekap, Nikolaos Simiriotis, Jean-Baptiste Tô, Jean-François Rouchon, Yannick Hoarau and Marianna Braza

The purpose of this study illustrates the morphing effects around a large-scale high-lift configuration of the Airbus A320 with two elements airfoil-flap in the take-off…

Abstract

Purpose

The purpose of this study illustrates the morphing effects around a large-scale high-lift configuration of the Airbus A320 with two elements airfoil-flap in the take-off position. The flow around the airfoil-flap and the near wake are analysed in the static case and under time-dependent vibration of the flap trailing-edge known as the dynamic morphing.

Design/methodology/approach

Experimental results obtained in the subsonic wind tunnel S1 of Institut de Mécanique des Fluides de Toulouse of a single wing are discussed with high-fidelity numerical results obtained by using the Navier–Stokes multi-block (NSMB) code with advanced turbulent modelling able to capture the predominant instabilities and coherent structure dynamics. An explanation of the dynamic time-dependent grid deformation is provided, which is used in the NSMB code to simulate the flap’s trailing-edge deformation in the morphing configuration. Finally, power spectral density is performed to reveal the coherent wake structures and their modification because of the morphing.

Findings

Frequency of vibration and amplitude of deformation effects are investigated for different morphing cases. Optimal morphing regions at a specific frequency and a slight deformation were able to attenuate the predominant natural shear-layer frequency and to considerably decrease the width of the von Kármán vortices with a simultaneous increase of aerodynamic performances.

Originality/value

The new concept of future morphed wings is proposed for a large scale A320 prototype at the take-off position. The dynamic morphing of the flap’s trailing-edge is simulated for the first time for high-lift two-element configuration. In addition, the wake analysis performed helped to show the turbulent structures according to the organised eddy simulation model.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 5 January 2015

Rongqi Shi and Weiyu Wan

This paper aims to clarify the flight dynamics characteristics and improve the flight performance for large-scale morphing aircrafts. With specific focus on the effects of…

Abstract

Purpose

This paper aims to clarify the flight dynamics characteristics and improve the flight performance for large-scale morphing aircrafts. With specific focus on the effects of morphing on mass distribution, aerodynamics and flight stability, the study aims to develop the dynamic model, outline the morphing strategies design and evaluate the flight stability in transient stage of morphing.

Design/methodology/approach

The mode of relaxing the rigidity condition was opted, which introduced the functions of position of center of mass and moments of inertia with respect to the morphing parameters, and yielded a parameter-dependent flight dynamics model. The morphing strategies were designed by optimizing the morphing parameters with the corresponding performance metric of each mission segment, where the aerodynamics was estimated concurrently by DATCOM. Based on the decoupled and linearized longitudinal parameter-dependent model, the flight stability in transient stage of morphing was evaluated based on Hurwitz rules, with the stability condition proposed.

Findings

The research suggests that the longitudinal flight stability in transient stage of morphing can be evaluated by the relationship of aerodynamic pitching moment derivatives and the effects of morphing on the mass distribution, which results in a constraint on the morphing rate.

Research limitations/implications

The aerodynamics is computed under quasi-steady aerodynamic assumption in low morphing rate and only the longitudinal flight stability is analyzed. Therefore, researchers are encouraged to evaluate the lateral stability and aerodynamics in high morphing rate.

Practical implications

The paper includes implications for the improvement of the flight performance of a multi-mission morphing aircraft and the design of the flight control system.

Originality/value

Methods of dynamic modeling and morphing strategies design are proposed for large-scale morphing aircrafts, and the condition of flight stability in transient stage of morphing is obtained. The results provide reference to research works in the field of dynamics and control of large-scale morphing aircrafts.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 87 no. 1
Type: Research Article
ISSN: 0002-2667

Keywords

Article
Publication date: 3 October 2016

Marco Evangelos Biancolini, Emiliano Costa, Ubaldo Cella, Corrado Groth, Gregor Veble and Matej Andrejašič

The present paper aims to address the description of a numerical optimization procedure, based on mesh morphing, and its application for the improvement of the aerodynamic…

Abstract

Purpose

The present paper aims to address the description of a numerical optimization procedure, based on mesh morphing, and its application for the improvement of the aerodynamic performance of an industrial glider which suffers of a large separation occurring in the wing–fuselage junction region at high incidence angles.

Design/methodology/approach

Shape variations were applied to the baseline configuration through a mesh morphing technique founded on the mathematical framework of radial basis functions (RBF). The aerodynamic solutions were obtained coupling an RANS code with the mesh morphing tool RBF Morph™. Two shape modifiers were set up to generate a parametric numerical model. An optimization procedure, based on a design of experiment sampling, was set up implementing the fully automated workflow within a high performance computing (HPC) environment. The optimal candidates maximizing the aerodynamic efficiency were identified by means of a cubic RBF response surface approach.

Findings

The separation was significantly reduced, modifying the local geometry of fuselage and fairing and maintaining the wing aerofoil unchanged. A relevant aerodynamic efficiency improvement was finally gained.

Practical implications

The developed procedure proved to be a very powerful and efficient tool in facing aerodynamic design problems. However, it might be computationally very expensive if a large number of design variables are adopted and, in those cases, the method can be suitably used only within the HPC environment.

Originality/value

Such an optimization study is part of an explorative set of analyses that focused on better addressing the numerical strategies to be used in the development of the EU FP7 Project RBF4AERO.

Details

Aircraft Engineering and Aerospace Technology, vol. 88 no. 6
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 2 November 2018

Jinwu Xiang, Kai Liu, Daochun Li, Chunxiao Cheng and Enlai Sha

The purpose of this paper is to investigate the unsteady aerodynamic characteristics in the deflection process of a morphing wing with flexible trailing edge, which is…

383

Abstract

Purpose

The purpose of this paper is to investigate the unsteady aerodynamic characteristics in the deflection process of a morphing wing with flexible trailing edge, which is based on time-accurate solutions. The dynamic effect of deflection process on the aerodynamics of morphing wing was studied.

Design/methodology/approach

The computational fluid dynamic method and dynamic mesh combined with user-defined functions were used to simulate the continuous morphing of the flexible trailing edge. The steady aerodynamic characteristics of the morphing deflection and the conventional deflection were studied first. Then, the unsteady aerodynamic characteristics of the morphing wing were investigated as the trailing edge deflects at different rates.

Findings

The numerical results show that the transient lift coefficient in the deflection process is higher than that of the static case one in large angle of attack. The larger the deflection frequency is, the higher the transient lift coefficient will become. However, the situations are contrary in a small angle of attack. The periodic morphing of the trailing edge with small amplitude and high frequency can increase the lift coefficient after the stall angle.

Practical implications

The investigation can afford accurate aerodynamic information for the design of aircraft with the morphing wing technology, which has significant advantages in aerodynamic efficiency and control performance.

Originality/value

The dynamic effects of the deflection process of the morphing trailing edge on aerodynamics were studied. Furthermore, time-accurate solutions can fully explore the unsteady aerodynamics and pressure distribution of the morphing wing.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

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