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The paper deals with a new morphing wing application developed with a full-scale portion of a regional aircraft. Shown are: the design of the control system for the actuation mechanism based on four miniature high-force in-house developed electrical actuators, the testing of the controlled morphing wing on bench and wind tunnel, and the evaluation of the aerodynamic gain of the morphing wing technology on the experimental model (pressure signals analysis, and infra-red thermography visualizations)., 30th International Conference on Adaptive Structures and Technologies, ICAST 2019, October 7-11, 2019, Montreal, Canada

Dans ce travail, les études numériques et analytiques ont été réalisés pour évaluer l’effet de la trainée de forme Darcy-Dupuit convection dans une cavité poreuse horizontale rectangulaire saturée par un fluide, soumise à un gradient thermique vertical. L’effet de la trainée de forme sur le seuil de bifurcation Hopf (caractérisant le point de transition entre la solution permanente et oscillante de la convection) a été aussi étudié. Pour une cavité carrée l’analyse de transition d’écoulement est réalisée en considérèrent les flux convectifs mon-cellules ou multi-cellules. Les paramètres régissant ce phénomène sont le nombre de Rayleigh, RT, le rapport de forme, A, et le coefficient de la trainée de forme caractérisée par le nombre de Prandtl modifié, * r P . Pour une couche poreuse élancée (A>>1), on a utilisé l’hypothèse de l’écoulement parallèle afin d’obtenir une solution analytique dans les deux cas (milieu poreux Darcy, milieu poreux Dupuit-Darcy. Les méthodes numériques (ADI et SOR) basées sur la méthode des différences fines sont employées pour obtenir des solutions numériques des équations gouvernantes générales., La 1ère Conférence Nationale sure les CFD et Technologie: CFD et Tech 2016, les 2 et 3 mai 2016, CRN Draria, Alger

National audience; La diversité et la distribution géographique des musaraignes du Maghreb restent mal connues. Ainsi, de récentes analyses moléculaires ont signalé pour la première fois Crocidura pachyura en Kabylie, alors qu’au Maroc c’est C. russula qui serait présente. La distribution précise de ces deux espèces soeurs est encore mal connue, ainsi que leur variabilité morphologique. Afin de comparer leur morphologie et de préciser leurs limites de distribution, ce travail porte sur l’étude morphométrique de 545 spécimens provenant de 7 localités d’Algérie et de 10 localités du Maroc. Une partie des spécimens (173 individus) est issue de plusieurs méthodes de piégeage (pots enterrés, pièges Sherman) et l’autre (372 individus fragmentés) provient de pelotes de rejections de rapace (en particulier Tyto alba). Une analyse exploratoire a été effectuée sur huit mesures de distance prises sur la mandibule gauche de spécimens séquencés (93 spécimens) et non séquencés (80). Les premières analyses multivariées (AFD, ACP) montrent que C. pachyura est plus grande que C. russula, mais une variabilité morphométrique importante est présente chez les deux espèces. Des différences de forme entre les deux espèces sont constatées.

Aerodynamic testing of high fidelity models is a standard practice for aircraft manufacturers. With the development of phased microphone array technology, aeroacoustics can become an integral part of the design process of an airplane. In 2012, the National Research Council Canada and Bombardier Aerospace carried out a collaborative research program focusing on measuring the sound generated by a high-fidelity aerodynamic wind tunnel model. The noise of various configurations was measured at combinations of three wind speeds and three microphone array polar orientations above the model. Several calibration reference noise waveforms were explored to determine the most effective in a highly reverberant hard-walled test section. The calibration data analysis showed that meaningful beamform maps above 30kHz could be generated when a pulsed sine wave was applied as the reference noise signal in the calibration process. For the model configurations tested, slat noise dominated the sound maps processed using either conventional beamforming or CLEAN-PSF. The wing flap edge noise as well as the contributions from the main gear were also discernible. For each configuration, one data point was taken while the microphone array was rotating instead of stationary. The computationally intense post-processing procedure for these data provided a detailed map of the sources due to reduced spatial aliasing. The sound levels measured with the rotating array were at a slightly lower magnitude owing to the averaging of the source over its full directivity pattern. Future work includes implementing a calibration procedure for the rotating array and improving the signal-to-noise ratio of the signals so that shorter microphone time histories can be used to extract directivity information from the datasets of the rotating array., 19th AIAA/CEAS Aeroacoustics Conference, 27 May 2013 through 29 May 2013, Berlin

The main objectives of this research work are: the design and the wind tunnel testing of a controller for a new morphing mechanism using smart materials made of Shape Memory Alloy (SMA) for the actuators, and the aero-elasticity studies for the morphing wing. The finally obtained configuration for the controller is a combination of a bi-positional controller (on-off) and a PI (proportional-integral) controller, due to the two phases (heating and cooling) of the SMA wires' interconnection. Firstly, the controller is used for the open loop development step of a morphing wing project, while, further, it is included as an internal loop in the closed loop architecture of the morphing wing system. In the controller design procedure four step are considered: 1) SMA actuators model numerical simulation for different loading force cases; 2) linear system approximation in the heating and cooling phases using Matlab's System Identification Toolbox and the numerical values obtained in the first step; 3) selecting the controller type and its tuning for each of the two SMA actuators' phases - heating and cooling; and 4) integration of the two controllers just obtained into a single controller. For the controller validation three actions are taken: 1) numerical simulation; 2) bench testing; and 3) wind tunnel testing. For the third part of this study, aeroelastic studies, the purpose is to determine the flutter conditions in order to be avoided during wind tunnel tests. These studies show that aeroelastic instabilities for the morphing configurations considered appears at Mach number 0.55, which is higher than the wind tunnel Mach number limit speed of 0.3. © 2011 by Ruxandra Botez., AIAA Atmospheric Flight Mechanics Conference 2011, 8 August 2011 through 11 August 2011, Portland, OR

The Third International Thermal Energy Congress, Kitayushu, Japan, available, unclassified, unlimited

26th International Congress of the Aeronautical Sciences (from 9/14/2008 to 9/19/2008), Anchorage, Alaska, available, unclassified, unlimited

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BBAA VI International Colloquium on Bluff Bodies Aerodynamics & Applications Milano Italy (from 7/20/2008 to 7/24/2008), Milano Italy, available, unclassified, unlimited

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