Amélioration des performances par l'emploi de la technologie du morphing pour une aile d'avion de transport régional turbopropulsé

This article presents some application of the morphing technology for aerodynamic performance improvement of turboprop regional aircraft. It summarizes the results obtained in the framework of Clean Sky 2 REG-IADP AIRGREEN2 program on the development and application of dedicated morphing devices for take-off and landing, and their uses in off design conditions. The wing of the reference aircraft configuration considers Natural Laminar Flow characteristics. A deformable leading edge morphing device (“drooped nose”) and a multi functional segmented flap system have been considered. For the drooped nose, the use of deformable compliant structure was considered, as it allows a “clean” leading edge when not used, which is mandatory to keep NLF properties at cruise. The use of a segmented flap makes possible to avoid external flap track fairings, which will lead to performance improvement at cruise. An integrated tracking mechanism is used to set the flap at its take-off optimum setting, and then, morphing is applied in order to obtain high performance level for landing. Finally, some performance improvements can be obtained in climb conditions by using the last segment of the flap system to modify the load distribution on the wing in order to recover some extended laminar flow on the wing upper surface

Entrée en « modernité »

L’ouvrage de Pierre-Joseph Laurent recèle une profusion de données ethnographiques sur laquelle se bâtissent son exposé et son raisonnement. Cette multitude d’informations enrichit le lecteur d’une expérience qui, s’il l’acquiert par procuration, n’en est pas moins vivante ; cette abondance constitue aussi pour lui une difficulté. En effet, le foisonnement de l’ouvrage en dilue, ou plus exactement en éclate, le propos : quel est le sujet de cette somme de plus de quatre cents pages? Certes, l..

Aerodynamic Shape Design and Validation of an Advanced High-Lift Device for a Regional Aircraft with Morphing Droop Nose

In the present work, the aerodynamic shape design of an advanced high-lift system for a natural laminar flow (NLF) wing, based on the combination of a morphing droop nose and a single slot trailing edge flap, is presented. The paper presents both the aerodynamic design and optimization of the NLF wing and the high-lift configuration considering the mutual effects of both flap devices. Concerning the morphing droop nose (DN), after defining the parameterization techniques adopted to describe the geometry in terms of morphing shape and flap settings, the external configuration is obtained by an aerodynamic shape optimization procedure able to meet geometrical constraints and the skin structural requirements due to the morphing. The final performance assessment of the three-dimensional high-lift configurations is performed by high-fidelity aerodynamic analyses. The design procedure is applied to a twin-prop regional aircraft equipped with a natural laminar flow wing. The morphing droop nose is compatible with an NLF wing that requires the continuity of the skin and, at the same time, extends the possibilities to improve the performances of the class of regional aircraft which usually are not equipped with conventional leading edge devices. Additionally, the morphing technology applied to the flap allows the design of a tracking system fully integrated inside the airfoil geometry, leading to a solution without external fairings and so with no extra friction drag penalty for the aircraft

Métamorphose d’un sacrement. La communion, de la pratique socialisée à la participation sensible

Dans le cadre d’une enquête sur la pratique et les usages catholiques dans une ville belge (Charleroi), il a été constaté qu’au sein des pratiquants dominicaux la proportion de ceux qui communient est considérablement plus élevée qu’elle ne l’était lors d’une enquête similaire réalisée quarante ans auparavant (89,6.% contre seulement 27,3.%). Cet écart significatif souligne les métamorphoses de la religiosité .; cadres institutionnels, interprétation du dogme et sens de la pratique sont profondément transformés et radicalement recomposés. L’acte de communier est, aujourd’hui, la norme pour tous ceux qui assistent à la messe alors qu’hier, par le faible taux de communion et par sa variation entre catégories, l’évidence était ailleurs, dans l’expérience d’une communauté. Se dessine une intelligibilité de la modernité où les mécanismes de signification et de religiosité accomplissent leur pleine socialisation : ils deviennent individuels dans une société qui ne reconnaît plus que l’individu.Within the context of a survey on Catholic practices and customs in a Belgian city (Charleroi), it has been noted that among Sunday churchgoers, the proportion of those receiving communion is considerably higher than was the case in a similar survey carried out forty years before (89.6% as against 27.3%). This significant difference emphasises the metamorphoses of religiosity. Institutional framework, the interpretation of the dogma, and the meaning of church attendance are profoundly transformed and radically reconstructed. Receiving communion today is the norm for those who go to mass, whereas yesterday, given the low rate of communion and its variation across categories, the evidence was elsewhere, i.e. in a community’s experience. An emergent intelligibility of modernity may be noted, where the mechanisms of meaning and religiosity achieve their full socialisation. They become individual in a society which only recognises the individual.En el marco de una investigación sobre las prácticas y las costumbres católicas en una ciudad belga (Charleroi), se ha constatado que, entre los practicantes dominicales, el porcentaje de los que comulgan es mucho más elevado de lo que era en una investigación semejante realizada hace 40 años (un 89,6.% contra sólo un 27,3.%). Esta diferencia significativa subraya las metamórfosis de la religiosidad ; marcos institucionales, interpretación del dogma y sentido de la práctica están profundamente transformados y radicalmente recompuestos. Hoy en día el acto de comulgar es la norma para los que van a misa mientras que ayer, en vista de la baja tasa de comunión y su variación entre categorías, la evidencia radicaba en otra parte, en la experiencia de una comunidad. Se perfila una inteligibilidad de la modernidad en que los mecanismos de significado y religiosidad desempeñan su plena socialización : se hacen individuales en una sociedad que sólo conoce al individuo

Amélioration des performances d'un avon régional par l'utilisation de riblets et de la technologie NLF

International audienceThe application of riblets on a typical regional turboprop configuration is discussed in this paper. The effect of the riblets is modeled as a singular roughness problem by a proper boundary condition at the wall. The model, already proposed in a previous paper, is briefly described. The drag prediction capabilities are verified by showing some airfoil flow applications. Then a typical wing-body of a regional aircraft is considered. The configuration has been designed to have extended natural laminar flow in cruise conditions. Riblets are applied at flow specifications representative of cruise in combination with the natural laminar flow technology and in climb/descent conditions. A comparison of the two technologies in terms of drag reduction is presented. Their combined application can result in a cruise drag reduction of more than 20%. The resulting fuel savings during a typical operational day are evaluated

Lessons Learnt from Chimera Method Application to a Deploying Krueger Device

The Chimera method [1] is an established method for simulation of overlapping grids. Meshing parts independently has made this method popular for complex geometries as well as moving bodies like propellers and rotors (e.g. [2]) or control surfaces (e.g. [3]). It is thus a promising method to simulate deflecting high-lift systems. The motion of the Krueger flap – as the most promising leading edge high-lift system device for laminar wing technology – is characterized by a relatively large movement (about 140 deg deflection) at a relatively high deflection speed (up to 200 deg/s) compared to classical leading edge devices. In terms of simulation, the grid properties of the overlapping mesh regions vary throughout the motion from a nearly sealed retracted position to a gapped flow in fully deflected position comparable to a slat device. This expects dynamic effects may get dominant and a valid simulation of this flow is needed for proper design and analysis. In the frame of the UHURA project1 , several partners applied their CFD capabilities based on Chimera in order to validate the method for this specific application in comparison to wind tunnel tests. The presentation outlines the different Chimera approaches ranging from structured/2D to hybrid/3D in steady and unsteady simulations for the different type of setups investigated, namely straight and swept wing with full-span and part-span Krueger flap. It summarizes common challenges and best practice for application of the Chimera approach for such a device.&nbsp

Lessons Learnt from Chimera Method Application to a Deploying Krueger Device

The Chimera method is an established method for simulation of overlapping grids. Meshing parts independently has made this method popular for complex geometries as well as moving bodies like propellers and rotors or control surfaces. It is thus a promising method to simulate deflecting high-lift systems. In the frame of the UHURA project, several partners applied their CFD capabilities based on Chimera in order to validate the method for this specific application in comparison to wind tunnel tests. The presentation outlines the different Chimera approaches ranging from structured/2D to hybrid/3D in steady and unsteady simulations for the different type of setups investigated, namely straight and swept wing with full-span and part-span Krueger flap. It summarizes common challenges and best practice for application of the Chimera approach for such a device

A Validation Program for Dynamic High-Lift System Aerodynamics

The feasibility of laminar flow control technology for future wing is bound to the development of a leading edge high-lift system that complies with the requirements on smooth surfaces to enable maintaining the laminar boundary layer flow, such as a Krueger flap. Although in principle the aerodynamic performance of a Krueger flap is known, the unsteady behaviour of the flow during deployment and retraction is completely unknown. This is as even more important as during deployment the Krueger flap is exposed to highly unfavourable positions perpendicular to the flow. To mitigate the risk of unfavourable aircraft behaviour, it is therefore expected that a Krueger flap has to be deflected significantly fast and may trigger unsteady aerodynamic effects. The European H2020 project UHURA, running from September 2018 to August 2022, has been focusing on the unsteady flow behaviour around such high-lift system and will first time deliver a deeper understanding of critical flow features at this type of high-lift device during their deployment and retraction together with a validated numerical procedure for its simulation. UHURA performed detailed experimental measurements in several wind tunnels to obtain a unique data set for validation purposes of Computational Fluid Dynamics (CFD) software, including detailed flow measurements by Particle Image Velocimetry (PIV) and other optical measurement technologies. Advanced CFD methods promising significant improvements in the design lead time have been applied and validated against this database to obtain efficient and reliable prediction methods for design. This first contribution within the Special Technology Session provides an overview on the project. While the simulation activities are detailed in the forthcoming presentations, this presentation focusses on the experiments conducted to obtain a unique database for the validation of simulation methods for this kind of unsteady flows. Finally, an outlook is given on the validation and exploitation methodology applied in the last period of the project

The mitotic checkpoint is a targetable vulnerability of carboplatin-resistant triple negative breast cancers

Triple-negative breast cancer (TNBC) is the most aggressive breast cancer subtype, lacking effective therapy. Many TNBCs show remarkable response to carboplatin-based chemotherapy, but often develop resistance over time. With increasing use of carboplatin in the clinic, there is a pressing need to identify vulnerabilities of carboplatin-resistant tumors. In this study, we generated carboplatin-resistant TNBC MDA-MB-468 cell line and patient derived TNBC xenograft models. Mass spectrometry-based proteome profiling demonstrated that carboplatin resistance in TNBC is linked to drastic metabolism rewiring and upregulation of anti-oxidative response that supports cell replication by maintaining low levels of DNA damage in the presence of carboplatin. Carboplatin-resistant cells also exhibited dysregulation of the mitotic checkpoint. A kinome shRNA screen revealed that carboplatin-resistant cells are vulnerable to the depletion of the mitotic checkpoint regulators, whereas the checkpoint kinases CHEK1 and WEE1 are indispensable for the survival of carboplatin-resistant cells in the presence of carboplatin. We confirmed that pharmacological inhibition of CHEK1 by prexasertib in the presence of carboplatin is well tolerated by mice and suppresses the growth of carboplatin-resistant TNBC xenografts. Thus, abrogation of the mitotic checkpoint by CHEK1 inhibition re-sensitizes carboplatin-resistant TNBCs to carboplatin and represents a potential strategy for the treatment of carboplatin-resistant TNBCs