Publications de Philippe Meliga

Self-consistent triple decomposition of the turbulent flow over a backward-facing step under finite amplitude harmonic forcing

François Gallaire, Philippe Meliga, Eunok Yim

We investigate the saturation of harmonically forced disturbances in the turbulent flow over a backward-facing step subjected to a finite amplitude forcing. The analysis relies on a triple decomposition of the unsteady flow into mean, coherent and incohere ...

ROYAL SOC2019

Revisiting the drag reduction problem using adjoint-based distributed forcing of laminar and turbulent flows over a circular cylinder

François Gallaire, Philippe Meliga, Edouard Boujo

This study assesses the ability of a sensitivity-based, span-wise homogeneous control velocity distributed at the surface of a circular cylinder to cut down the cost of reducing drag by more classical techniques, e.g., base bleed and lateral suction. At Re ...

ELSEVIER SCIENCE BV2018

Numerical simulation and sensitivity analysis of a low-Reynolds-number flow around a square cylinder controlled using plasma actuators

François Gallaire, Philippe Meliga, Edouard Boujo

Flow around a square cylinder controlled using plasma actuators (PAs) is numerically investigated by direct numerical simulation in order to clarify the most effective location of actuator installation and to elucidate the mechanism of control effect. The ...

Amer Physical Soc2017

A self-consistent formulation for the sensitivity analysis of finite-amplitude vortex shedding in the cylinder wake

François Gallaire, Philippe Meliga, Edouard Boujo

We use the adjoint method to compute sensitivity maps for the limit-cycle frequency and amplitude of the Benard von Karmzin vortex street in the wake of a circular cylinder. rfhe sensitivity, analysis is performed in the frame of the semi-linear self consi ...

Cambridge University Press2016

Pushing amplitude equations far from threshold: application to the supercritical Hopf bifurcation in the cylinder wake

François Gallaire, Philippe Meliga, Edouard Boujo, Vladislav Mantic Lugo, Cristobal Manuel Arratia Martinez

The purpose of this review article is to push amplitude equations as far as possible from threshold. We focus on the Stuart-Landau amplitude equation describing the supercritical Hopf bifurcation of the flow in the wake of a cylinder for critical Reynolds ...

Iop Publishing Ltd2016

Sensitivity of aerodynamic forces in laminar and turbulent flow past a square cylinder

François Gallaire, Philippe Meliga, Edouard Boujo

We use adjoint-based gradients to analyze the sensitivity of the drag force on a square cylinder. At Re = 40, the flow settles down to a steady state. The quantity of interest in the adjoint formulation is the steady asymptotic value of drag reached after ...

2014

Marangoni induced force on a drop in a Hele Shaw cell

François Gallaire, Philippe Meliga

We analyse the force balance on a cylindrical drop in a Hele-Shaw cell, subjected to a Marangoni flow caused by a surface tension gradient. Depth-averaged Stokes equations, called Brinkman equations, are introduced and a general closed form solution is obt ...

American Institute of Physics2014

Sensitivity of aerodynamic forces in laminar and turbulent flow past a square cylinder

François Gallaire, Philippe Meliga, Edouard Boujo

We use adjoint-based gradients to analyze the sensitivity of the drag force on a square cylinder. At Re = 40, the flow settles down to a steady state. The quantity of interest in the adjoint formulation is the steady asymptotic value of drag reached after ...

Amer Inst Physics2014

A weakly nonlinear mechanism for mode selection in swirling jets

François Gallaire, Philippe Meliga

Global linear and nonlinear bifurcation analysis is used to revisit the spiral vortex breakdown of nominally axisymmetric swirling jets. For the parameters considered herein, stability analyses single out two unstable linear modes of azimuthal wavenumber m ...

Cambridge University Press2012

Global modes in a confined impinging jet: application to heat transfer and control

Philippe Meliga

We investigate the stability and control of a plane, laminar jet impinging on a flat plate in a channel, a geometry used to cool down a hot wall with a cold air jet in many industrial configurations. The global stability analysis indicates that, even for a ...

Springer-Verlag2011

Extracting energy from a low Reynolds-number-flow using vortex-induced vibrations and optimal control theory

Philippe Meliga

Elsevier2011

Control of axisymmetric vortex breakdown in a constricted pipe: Nonlinear steady states and weakly nonlinear asymptotic expansions

François Gallaire, Philippe Meliga

The present paper investigates numerically and theoretically the axisymmetric vortex breakdown occurring in a constricted pipe of infinite extension, i.e., the transition from a smooth columnar state to a breakdown state exhibiting a recirculation bubble. ...

2011

Open-loop control of compressible afterbody flows using adjoint methods

Philippe Meliga

The flow past an axisymmetric body is generically unstable to a steady and a time-periodic global instability, the latter being thought to lead the low-frequency unsteadiness of the wake even at larger Reynolds numbers. The present paper examines how the g ...

2010