ESPCI web site
Le séminaire hebdomadaire du laboratoire PMMH a lieu tous les vendredis à 11h, au premier étage Barre Cassan, campus Jussieu (plan).
Contact :
Stéphane Perrard
Etienne Reyssat
Virgile Thiévenaz
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
Séminaire PMMH - Edouard Ravier (Université du Mans)
Vendredi 3 décembre 2021 de 11h00 à 12h00 - Salle réunion PMMH 1
What can we learn from the experimental modelling of subglacial hydrology ?
The configuration and evolution of the hydrological system under ice sheets is a key control on ice flow dynamics, erosion, sedimentation and bed deformation. Due to the inaccessibility of the subglacial environment, the understanding of subglacial meltwater drainage and its interaction with the ice and the substratum often relies on numerical modelling and/or analyses of palaeo-ice sheet beds (e.g., geomorphology, sedimentology).
We introduce an innovative and unique experimental model to examine erosion and deformation of the subglacial bed by circulation of pressurized meltwater at the ice/substratum interface. We use a permeable substratum (sand) simulating the subglacial bed partially covered by a viscous, impermeable, and transparent silicon putty cap simulating the ice, below which we apply a central injection of pure water. Modelling results show the formation of drainage landforms and bedforms that are morphologically similar to their natural counterparts observed beneath palaeo-ice sheets. By improving the monitoring devices, we can record the conditions and processes under which the experimental landforms and bedforms develop (deformation of the silicon, silicon flow velocity, drainage configuration, fluid pressure) and apply our findings to ancient and modern ice sheets. These findings are very promising and allow the processes of formation of subglacial valleys, the cycles of ice sheet stabilization/destabilization, the formation of subglacial bedforms or the position of large meltwater drainage routes to be re-investigated.
We introduce an innovative and unique experimental model to examine erosion and deformation of the subglacial bed by circulation of pressurized meltwater at the ice/substratum interface. We use a permeable substratum (sand) simulating the subglacial bed partially covered by a viscous, impermeable, and transparent silicon putty cap simulating the ice, below which we apply a central injection of pure water. Modelling results show the formation of drainage landforms and bedforms that are morphologically similar to their natural counterparts observed beneath palaeo-ice sheets. By improving the monitoring devices, we can record the conditions and processes under which the experimental landforms and bedforms develop (deformation of the silicon, silicon flow velocity, drainage configuration, fluid pressure) and apply our findings to ancient and modern ice sheets. These findings are very promising and allow the processes of formation of subglacial valleys, the cycles of ice sheet stabilization/destabilization, the formation of subglacial bedforms or the position of large meltwater drainage routes to be re-investigated.
Fig. 1. The array of experimental data produced by the physical model developed in le Mans Université. The physical modal is able to reproduce and monitor ice-water-sediments interactions.
Séminaires (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 (…)
Instructions générales pour les conférenciers
Le public du séminaire est très hétérogène (rien qu’au PMMH nous travaillons sur des thématiques très diverses, mécanique des fluides, des milieux granulaires, des solides, physique statistique, physique du mouillage, micro-fluidique, biophysique,...) l’objectif est donc de ne pas faire un séminaire trop spécialiste : au moins la première moitié du séminaire à un niveau accessible pour celui qui ne connaît rien sur le sujet.
Le séminaire a lieu à 11h. rendez-vous 15 minutes avant pour installer et tester la projection.
Le séminaire dure environ 45 minutes pour laisser un peu de temps pour discuter à la fin.
D’autres séminaires en région parisienne :
- 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
Lien vers séminaires café (internes, tous les jeudis)
