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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.

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.

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.

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.

This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 10⁶, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.

This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.

This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.

This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.

This study aims to investigate the effects of electroactive morphing on the Airbus A320 Reduced Scale prototype of the H2020 N° 723402 European Research project smart morphing and sensing (SMS) for aeronautical configurations [1]^,[2].

The flow regimes correspond to low subsonic take-off conditions. The morphing is applied through the vibration and slight deformation of the near trailing edge region; respecting the way, this actuation has been applied on the experimental prototype using micro fibre composite actuators. Optimal frequency range has been used, associated with low amplitudes of deformation with the Arbitrary Lagrangian Eulerian methodology. This study used an adapted turbulence modelling with the organised eddy simulation (OES) as well as a hybrid approach delayed detached eddy simulation – with embedded OES (DDES–OES), able to sensitise and keep up the coherent structures development.

The morphing at an optimal frequency (300 Hz) and amplitude (0.7 mm), applied on a length (3.5 cm) near the trailing edge, has been studied at Reynolds number 1 million and incidence of 10°. The effects on the main flow instabilities and on the turbulent vortex structures are analysed using proper orthogonal decomposition. A modification of the wake structures and a formation of organised rows of vortices along the shear layer are obtained. This leads to a quasi-two-dimensional wake, benefits on the aerodynamic performance and a decrease of the frequency peaks in the spectrum, corresponding to an attenuation of the coherent structures.

This study provides a fundamental understanding of how the actuation modifies the coherent and turbulent vortex structures around the wing and in the wake.

This study aims to investigate the physical mechanisms of the use of active flow control (AFC) for a high-lift wing-flap configuration.

By means of high-fidelity numerical simulations, the flow dynamics around a high-lift wing-flap system at high Reynolds number (Re/c = 4.6 million) is studied. Adapted turbulence models based on the URANS approach are used to capture the flow separation and the subsequent development of coherent structures. The present study focuses on the use of AFC using a synthetic jet known as zero-net-mass-flux (ZNMF) using the blowing–suction approach. Different parameters (geometry, frequency and velocity) of a ZNMF placed at the cambered flap’s chord are optimized to obtain the most efficient parameter settings to suppress the flow separation.

A synthetic jet with the optimal shape and orientation enforces the flow reattachment on the wing-flap surface. This leads to an improvement of the aerodynamic performance of the system. The wake thickness was reduced by 30%, and an increase of 17.6% in lift-to-drag ratio was obtained. Concerning the ZNMF location, they should be installed upstream of the separation point to achieve the best performance.

The effectiveness of ZNMF devices integrated on a high-lift wing-flap configuration was studied in real flight conditions at high Reynolds number. A detailed analysis of the wake dynamics explains how AFC forces the reattachment of the boundary layer and attenuates the predominant wake instabilities up to −20 dB.

This paper aims to assess the strengths and weaknesses of four thermodynamic models used in aircraft icing simulations to orient the development or the choice of an improved thermodynamic model.

Four models are compared to assess their capabilities: Messinger, iterative Messinger, extended Messinger and shallow water icing models. They have been implemented in the aero-icing framework, NSCODE-ICE, under development at Polytechnique Montreal since 2012. Comparison is performed over typical rime and glaze ice cases. Furthermore, a manufactured geometry with multiple recirculation zones is proposed as a benchmark test to assess the efficiency in runback water modeling and geometry evolution.

The comparison shows that one of the main differences is the runback water modeling. Runback modeling based on the location of the stagnation point fails to capture the water film behavior in the presence of recirculation zones on airfoils. However, runback modeling based on air shear stress is more suitable in this situation and can also handle water accumulation while the other models cannot. Also, accounting for the conduction through the ice layer is found to have a great impact on the final ice shape as it increases the overall freezing fraction.

This paper helps visualize the effect of different thermodynamic models implemented in the same aero-icing framework. Also, the use of a complex manufactured geometry highlights weaknesses not normally noticeable with classic ice accretion simulations. To help with the visualization, the ice shape is presented with the water layer, which is not shown on typical icing results.

The transonic buffet is a complex aerodynamics phenomenon that imposes severe constraints on the design of high-speed vehicles, including for aircraft and space launchers. The origin of buffet is still debated in the literature, and the control of this phenomenon remains difficult. This paper aims to propose an original scenario to explain the origin of buffet, which in turn opens promising perspectives for its alleviation and attenuation.

This work relies on the use of numerical simulations, with the idea to reproduce the buffet phenomenon in a transonic aileron designed for small space launchers. Two numerical approaches are tested: unsteady Reynolds averaged Navier–Stokes (URANS) and large-eddy simulation (LES). The numerical predictions are first validated against available experimental data, before to be analysed in detail to identify the origin of buffet on the studied configuration. A complementary numerical study is then conducted to assess the possibility to delay the onset of buffet.

The buffet control strategy is based on wall cooling. By adequately choosing the wall temperature, this work shows that it is feasible to delay the emergence of buffet. More precisely, this paper highlights the crucial role of the subsonic flow inside the boundary layer, showing the existence of upstream travelling pressure waves that are responsible for the flow coupling between both sides of the airfoil, at the origin of the buffet phenomenon.

This paper proposes a new scenario to explain the origin of buffet, based on the use of a Fanno and Rayleigh flow analogies. This approach is used to design a control solution based on a modification of the wall temperature, showing very promising results.