ESPCI web site
PMMH’s weekly seminar is held every Friday at 11 am (map)
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
PMMH
BARRE CASSAN
BAT A 1ER ETAGE CASE 18
7 QUAI SAINT BERNARD
75005 PARIS
France
Tel : (33) 1 40 79 45 22
Xavier Garnaud (LadHyX, École Polytechnique)
Global instabilities of subsonic jets
The stability of spatially developing subsonic jets is investigated. If the density ratio between the jet and the outside is sufficiently low, arbitrarily small perturbations grow in time until self sustained oscillation appear in the non-linear regime. Both the apparition of these structures and their frequency is well explained by a local instability argument.
In an isothermal setting on the contrary all eigenmodes are found to be stable, meaning that perturbations eventually decay at long times. While this observation is in agreement with classical local stability results, a stable eigen-mode spectrum seems inappropriate for the description of the convective instability dynamics of jets, which are known to be highly receptive to external perturbations. Instead, we propose to characterize jet instability in terms of the linear flow response to time-harmonic forcing. External perturbations inside the nozzle duct are identified that give rise to the most amplified flow response at a prescribed frequency.
Séminaires du laboratoire PMMH : consultez le programme
- Seminar archive
- Recent seminars
- Seminars
Seminars (4)
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Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…) -
Séminaire PMMH - Francesca Borghi Università degli Studi di Milano
Vendredi 20 juin de 11h00 à 12h00 - Salle réunion PMMH 1
REPROGRAMMABLE HARDWARE FOR DATA PROCESSING AT THE EDGE : A NEW COMPUTING PARADIGM BASED ON NEUROMORPHIC SYSTEMS
The brain's ability to perform efficient and fault-tolerant data processing is strongly related with its peculiar interconnected adaptive architecture, based on redundant neural circuits interacting at different scales. By emulating the brain's processing and learning mechanisms, computing technologies strive to (…) -
Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…) -
Séminaire PMMH - Salvatore Federico (University of Calgary, Canada)
Vendredi 4 juillet de 11h00 à 12h00 - Salle réunion PMMH 1
Continuum Mechanics of Hydrated Fibre-Reinforced Soft Tissues
Biological tissues can be represented as bi-phasic continua, with a porous solid phase saturated by an interstitial fluid and reinforced by collagen fibers. This lecture will give an overview of the modelling techniques for fibre-reinforced porous composite materials with statistical orientation of the fibers. Both (…)
The audience is composed of people with rather heterogeneous backgrounds including specialists in solids, fluids, granular flows, statistical physics... so the idea is to keep your talk understandable by people not necessarily working in your field... The seminar time slot runs from 11am to noon so the best is to make the talk last around 45 minutes to leave some time for discussion.
- Séminaires ESPCI-ENS de biophysique
- Séminaires du Département de Physique de l’ENS
- Séminaires du Laboratoire d’Hydrodynamique de l’X
- Séminaire de Mécanique d’Orsay (page web FAST)
- Séminaire de Mécanique d’Orsay (page web LIMSI)
- Séminaire de Mécanique des Fluides de l’Institut Jean le Rond d’Alembert
- Séminaires du laboratoire MSC, Paris VII
- Séminaires Gulliver
Link to cofee seminar (internal, every Thursday)
