International audience
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August 2021 (v1)PublicationUploaded on: December 3, 2022
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July 2011 (v1)Report
Wing design in aerodynamics requires the definition of global geometrical characteristics, such as span, root/tip length ratio, angle of attack, twist angle, sweep angle, etc, as well as local geometrical features that determine the wing section. The objective of this study is to propose an efficient algorithm to achieve the optimization of...
Uploaded on: December 3, 2022 -
May 2018 (v1)Journal article
The objective of this work is to investigate a Discontinuous Galerkin (DG) method for compressible Euler equations, based on an isogeometric formulation: the partial differential equations governing the flow are solved on rational parametric elements, that preserve exactly the geometry of boundaries defined by Non-Uniform Rational B-Splines...
Uploaded on: March 25, 2023 -
2006 (v1)Report
Parameterization techniques commonly used in aerodynamic shape optimization are essentially general and multi-purpose approaches. As a consequence, they cannot be well suited to a particular shape optimization problem. The present study proposes a new method that adapts an initial and perhaps naïve parameterization of an aerodynamic shape by...
Uploaded on: October 11, 2023 -
September 18, 2019 (v1)Conference paper
This work aims at developping an efficient isogeometric approach to simulate compressible flows including shocks. The use of the classical isogeometric analysis method based on a finite-element formulation [1] is tedious in this context, due to the necessity to introduce suitable terms for stabilization and shock capturing. Therefore, an...
Uploaded on: December 4, 2022 -
2007 (v1)Report
In this paper, we address aerodynamic shape optimization problems including uncertain operating conditions. After a review of the possible approaches to take into account uncertainty, we propose to use meta-modeling techniques in order to develop a two-level modeling procedure for statistics estimation. Radial basis functions are employed to...
Uploaded on: February 28, 2023 -
October 3, 2013 (v1)Publication
Mes travaux de recherche concernent les méthodes pour la conception optimale en mécanique des fluides numérique. Il s'agit d'un contexte difficile, dans la mesure où l'évaluation de la fonctionnelle coût pour l'optimisation s'appuie sur la résolution des équations aux dérivées partielles régissant l'écoulement, caractérisées par de fortes non-...
Uploaded on: December 2, 2022 -
June 2015 (v1)Report
Sensitivity analysis is a key element in a design optimization procedure. Although the related theory and numerical implementation are well known for steady problems, the application to unsteady partial differential equations, in particular in fluid mechanics, is still an active research area.In this report, a sensitivity equation method is...
Uploaded on: March 25, 2023 -
September 2020 (v1)Journal article
This study concerns the development of a new method combining high-order CAD-consistent grids and adaptive refinement / coarsening strategies for efficient analysis of compressible flows. The proposed approach allows to use geometrical data from Computer-Aided Design (CAD) without any approximation. Thus, the simulations are based on the exact...
Uploaded on: December 4, 2022 -
May 2017 (v1)Conference paper
Sensitivity analysis for systems governed by partial differential equations is now commonly used by engineers to assess performance modification due to parameter changes. A typical illustration concerns shape optimization procedures based on the adjoint method, used in aeronautics to improve aerodynamic or structural performance of aircrafts....
Uploaded on: March 25, 2023 -
2009 (v1)Report
In this report, we present a new method, namely isogeometric analysis, proposed by T. Hughes and his collaborators, whose objective is to combine Computer Aided Design (CAD) tools and Finite-Element (FE) solvers into a single software entity. This consists in replacing grids by parametric surfaces and volumes to define the integration elements...
Uploaded on: December 3, 2022 -
2006 (v1)Report
Parameterization techniques commonly used in aerodynamic shape optimization are essentially general and multi-purpose approaches. As a consequence, they cannot be well suited to a particular shape optimization problem. The present study proposes a new method that adapts an initial and perhaps naïve parameterization of an aerodynamic shape by...
Uploaded on: December 3, 2022 -
September 12, 2019 (v1)Journal article
Nous sommes aujourd'hui habitués à voir des avions passer au dessus de nos têtes, si bien qu'on ne prend plus vraiment le temps de les observer. Pourtant, la forme des avions, et plus particulièrement la forme de leurs ailes, a significativement évolué avec les progrès des sciences et des techniques. Voyons ce qui motive ces évolutions et...
Uploaded on: February 28, 2023 -
October 2023 (v1)Report
Physics-Informed Neural Networks (PINNs) have emerged as a promising paradigm for modeling complex physical phenomena, offering the potential to handle diverse scenarios to simulate coupled systems. This is a supervised or unsupervised deep learning approach that aims at learning physical laws described by partial differential equations. This...
Uploaded on: October 11, 2023 -
July 2006 (v1)Journal article
The numerical simulation of aerodynamic stall control using a synthetic jet actuator is presented and the automatic optimization of the control parameters is investigated. Unsteady Reynolds-averaged Navier-Stokes equations are solved on unstructured grids using a near-wall low-Reynolds number turbulence closure to simulate the effects of a...
Uploaded on: February 27, 2023 -
April 2010 (v1)Book section
Optimization tools in engineering design often require a high computational cost. This cost originates from two main sources: First, the evaluation of the objective function involved in such problems is in general very expensive. Then, depending on the method employed and on the dimension of the design vector, the optimization procedure...
Uploaded on: December 4, 2022 -
May 2006 (v1)Journal article
This study concerns the simulation and optimization of stall control, using a synthetic jet. The flow is simulated by solving unsteady Reynolds-averaged Navier-Stokes equations with a near-wall low-Reynolds number turbulence closure. The flow around a NACA 0015 airfoil, including a synthetic jet located at 12% of the chord, is studied for a...
Uploaded on: February 27, 2023 -
June 2021 (v1)Journal article
The objective of the present work is to develop a new numerical framework for simulations including moving bodies, in the specific context of high-order meshes consistent with Computer-Aided Design (CAD) representations. Thus, the proposed approach combines ideas from isogeometric analysis, able to handle exactly CAD-based geometries, and...
Uploaded on: December 4, 2022 -
May 25, 2009 (v1)Conference paper
Dans cet article, nous proposons une approche multiniveau permettant d'accélérer les algorithmes d'optimisation classiques. Cette approche utilise les vecteurs propres de la matrice Hessienne de la fonction coût pour définir des sous-espaces de conception. La recherche de l'optimum est alors effectuée successivement dans ces sous-espaces de...
Uploaded on: February 28, 2023 -
December 2013 (v1)Report
A synthetic jet is an oscillatory jet, with zero time-averaged mass-flux, used to manipulate boundary layer characteristics for flow control applications such as drag reduction, detachment delay, etc. The objective of this work is the comparison and assessment of some numerical models of synthetic jets, in the framework of compressible flows...
Uploaded on: December 3, 2022 -
August 2012 (v1)Journal article
The automatic optimization of flow control devices is a delicate issue, due to the drastic computational time related to unsteady high-fidelity flow analyses and the possible multimodality of the objective function. Thus, we experiment in this article the use of kriging-based algorithms to optimize flow control parameters, since these methods...
Uploaded on: December 4, 2022 -
May 2022 (v1)Journal article
This work aims at developing a high-order, fully conservative, discretization of sliding grids with applications to compressible flows at different regimes (from subsonic to supersonic). The proposed approach combines a discontinuous Galerkin formulation for Navier-Stokes equations with rational representations originating from Isogeometric...
Uploaded on: December 3, 2022 -
June 15, 2020 (v1)Conference paper
We propose a Discontinuous Galerkin (DG) method for the numerical solution of the compressible Navier-Stokes equations with a functional representation derived from Computer Aided Design (CAD). The extraction of a set of DG-compliant basis functions from Non-Uniform Rational B-Splines (NURBS) is briefly discussed and the discretization of the...
Uploaded on: December 4, 2022