Research

JARDIN Thierry — 2014-10-08T13:40:49Z

Sommaire

Flapping & revolving wings

Collaborations : Institut Pprime (Laurent David), Caltech (Tim Colonius), Silmach (Jean-Renaud Frutos)

PhD student : Daniel Diaz

We investigate on the aerodynamics of natural flyers, such as hummingbirds, dragonflies or maple seeds. Of particular interests are (i) the dynamics of the leading edge vortex on revolving wings, (ii) fluid-structure interactions on flapping wings and (iii) the development of bio-inspired nano-flying-robots.

Highly maneuverable vehicles

Collaborations : ENAC (Murat Bronz), Delair-Tech (Stéphane Terrenoir)

PhD student : Yuchen Leng

Highly maneuverable vehicles undergo drastic changes in flight attitude, which favors highly unsteady aerodynamic phenomena. Added mass effects, massive flow separation and subsequent vortex-vehicle interactions may occur, which in turn affect the aerodynamic loads experienced by the vehicle. Here, we characterize these unsteady phenomena and develop reduced order models to predict the resulting forces (side-figure : credit Delair-Tech).

Compressible low Reynolds number flows

Collaborations : ONERA (Hervé Bézard)

PhD students : Laura-Victoria Rolandi, Thibault Désert

Recent applications such as flight on Mars and in the stratosphere or high speed trains in low-pressure tubes (hyperloop) require to understand the physics of compressible low-Reynolds number flows. Toward that end, we principally focus on (i) the fundamental analysis of bluff body wakes through linear stability approaches and Direct Numerical Simulations (DNS) and (ii) the development of Unmanned Air Vehicles (UAV) for Mars exploration.

Rotor aeroacoustics

Post-Doc fellows : Yeongmin Jo

Helicopter blades generate noise through complex aeroacoustic phenomena including blade-vortex interactions and shocks. These sources of noise may be mitigated and/or enhanced as Reynolds and Mach numbers are varied. We attempt to classify sources of noise as Reynolds and Mach numbers are decreased to values typical of flying taxis and drones using Large Eddy Simulations (LES) coupled with Ffowcs Williams and Hawkings approaches. These high-fidelity approaches are validated upon experimental tests conducted in anechoic room and compared with reduced order models (e.g. Blade Element Momentum Theory, Vortex Lattice Methods) which are then used to design aeroacoustically stealth rotors.

Publications

JARDIN Thierry — 2014-10-07T15:23:05Z

[26] Leng, Yuchen and Bronz, Murat and Jardin, Thierry and Moschetta, Jean-Marc. Slipstream Deformation of a Propeller-Wing Combination Applied for Convertible UAVs in Hover Condition. (2020) Unmanned Systems, 8 (4), 295-308.

[25] Alguacil, Antonio and Jardin, Thierry and Gourdain, Nicolas. Fluid–Structure Interactions and Unsteady Kinematics of a Low-Reynolds-Number Rotor. (2020) AIAA Journal, 58 (2), 955-967.

[24] Serré, Ronan and Gourdain, Nicolas and Jardin, Thierry and Jacob, Marc C. and Moschetta, Jean-Marc. Towards silent micro-air vehicles : optimization of a low Reynolds number rotor in hover. (2019) International Journal of Aeroacoustics, 18 (8), 690-710

[23] Prothin, Sebastien and Fernandez Escudero, Claudia and Doué, Nicolas and Jardin, Thierry. Aerodynamics of MAV rotors in ground and corner effect. (2019) International Journal of Micro Air Vehicles, 11, 1756829319861596.

[22] Jardin, Thierry and Doué, Nicolas. Influence of pitch rate on freely translating perching airfoils. (2019) Journal of Fluid Mechanics, 873. 49-71.

[21] Désert, Thibault and Jardin, Thierry and Bézard, Hervé and Moschetta, Jean-Marc. Numerical predictions of low Reynolds number compressible aerodynamics. (2019) Aerospace Science and Technology, 92. 211-223.

[20] Bensebaa, Tarek and Jardin, Thierry and Prothin, Sebastien and Doué, Nicolas. Rotor performance enhancement through blade surging. (2019) International Journal of Micro Air Vehicles, 11. 1756829319844275.

[19] Gourdain, Nicolas and Jardin, Thierry and Serre, Ronan and Prothin, Sébastien and Moschetta, Jean-Marc. Application of a lattice Boltzmann method to some challenges related to micro-air vehicles. (2018) International Journal of Micro Air Vehicles, 10 (3). 285-299. ISSN 1756-8293

[18] Jardin, Thierry and Colonius, Tim, On the lift-optimal aspect ratio of a revolving wing at low Reynolds number, (2018) Journal of the Royal Society Interface, 15 (143). 1-31. ISSN 1742-5689

[17] Gourdain, Nicolas and Deepali, Singh and Jardin, Thierry and Prothin, Sebastien. Analysis of the Turbulent Wake Generated by a Micro Air Vehicle Hovering near the Ground with a Lattice Boltzmann Method. (2017) Journal of the American Helicopter Society, 62 (4). 1-12. ISSN 0002-8711

[16] Jardin, Thierry. Coriolis effect and the attachment of the leading edge vortex. (2017) Journal of Fluid Mechanics, 820. 312-340. ISSN 0022-1120

[15] Jardin, Thierry and Prothin, Sebastien and García Magaña, Cristian. Aerodynamic Performance of a Hovering Microrotor in Confined Environment. (2017) Journal of the American Helicopter Society, 62 (2). 1-7. ISSN 0002-8711

[14] Jardin, Thierry and David, Laurent. Root Cutout Effects on the Aerodynamics of a Low-Aspect-Ratio Revolving Wing. (2017) AIAA Journal, 55 (8). 2717-2726. ISSN 0001-1452

[13] Jardin, Thierry and Doué, Nicolas and Prothin, Sebastien and Moschetta, Jean-Marc. Numerical analysis of pitching-rotor aerodynamics. (2016) Journal of Fluids and Structures, 62. 175-186. ISSN 0889-9746

[12] Jardin, Thierry and David, Laurent. Coriolis effects enhance lift on revolving wings. (2015) Physical Review E. 1-4. ISSN 1539-3755

[11] Jardin, Thierry and Grondin, Gilles and Gressier, Jérémie and Huo, Chao and Doué, Nicolas and Barènes, Roger. Revisiting Froude's Theory for Hovering Shrouded Rotor. (2015) AIAA Journal. 1-9. ISSN 0001-1452

[10] Jardin, Thierry and David, Laurent. Spanwise gradients in flow speed help stabilize leading-edge vortices on revolving wings. (2014) Physical Review E, 90 (1). ISSN 1539-3755

[9] Jardin, Thierry and Bury, Yannick. Distributed forcing of the flow past a blunt-based axisymmetric bluff body. (2014) Theoretical and Computational Fluid Dynamics, 28 (3). 259-266. ISSN 0935-4964

[8] Bury, Yannick and Jardin, Thierry and Klöckner, Andreas. Experimental investigation of the vortical activity in the close wake of a simplified military transport aircraft. (2013) Experiments in Fluids, 54. ISSN 0723-4864

[7] Bury, Yannick and Jardin, Thierry. Transitions to chaos in the wake of an axisymmetric bluff body. (2012) Physics Letters A, 376 (45). 3219-3222. ISSN 0375-9601

[6] Jardin, Thierry and Farcy, Alain and David, Laurent. Three-dimensional effects in hovering flapping flight. (2012) Journal of Fluid Mechanics, 702. 102-125. ISSN 0022-1120

[5] David, Laurent and Jardin, Thierry and Braud, Patrick and Farcy, Alain. Time-resolved scanning tomography PIV measurements around a flapping wing. (2012) Experiments in Fluids, 52 (4). 857-864. ISSN 0723-4864

[4] Jardin, Thierry and Bury, Yannick. Lagrangian and spectral analysis of the forced flow past a circular cylinder using pulsed tangential jets. (2012) Journal of Fluid Mechanics, 696. 285-300. ISSN 0022-1120

[3] Jardin, Thierry and Chatellier, Ludovic and Farcy, Alain and David, Laurent. Correlation between vortex structures and unsteady loads for flapping motion in hover. (2009) Experiments in Fluids, 47 (4-5). 655-664. ISSN 0723-4864

[2] David, Laurent and Jardin, Thierry and Farcy, Alain. On the non-intrusive evaluation of fluid forces with the momentum equation approach. (2009) Measurement Science and Technology, 20 (9). 1-11. ISSN 0957-0233

[1] Jardin, Thierry and David, Laurent and Farcy, Alain. Characterization of vortical structures and loads based on time-resolved PIV for asymmetric hovering flapping flight. (2009) Experiments in Fluids, 46 (5). 847-857. ISSN 0723-4864

Edito

JARDIN Thierry — 2014-10-07T15:20:54Z

Welcome !

Below are some cool pics illustrating current research and recent publications :

#4 Transitional flow past an SD7003 airfoil.

#3 Flow past an axisymmetric blunt-based bluff body.

#2 Separated flow past a cambered airfoil.

#1 Impulsive flow around a low aspect ratio revolving wing.