Ravelet, Florent, Chiffaudel, A., Daviaud, F.
Dans un écoulement de von Karman turbulent (Re = 10^6), on observe expérimentalement une bifurcation globale se traduisant par la coexistence de deux régimes turbulents pour une même valeur du...
Ravelet, Florent, Chiffaudel, A., Daviaud, F., Marié, Louis
pour un écoulement de von Karman fortement turbulent (Re=10^6), on observe trois états moyens possibles : un état qui restaure statistiquement les symétries du système, et deux états qui la...
Ravelet, Florent, Chiffaudel, A., Daviaud, F.
Dans un écoulement de von Karman turbulent (Re = 10^6), on observe expérimentalement une bifurcation globale se traduisant par la coexistence de deux régimes turbulents pour une même valeur du...
Ravelet, Florent, Chiffaudel, A., Daviaud, F., Marié, Louis
pour un écoulement de von Karman fortement turbulent (Re=10^6), on observe trois états moyens possibles : un état qui restaure statistiquement les symétries du système, et deux états qui la...
Traveling waves in a fluid layer subjected to a horizontal temperature gradient (2007)
We report experimental observations of traveling waves in a pure fluid with a free surface situated in a long container submitted to a horizontal temperature gradient perpendicular to its large...
Traveling waves in a fluid layer subjected to a horizontal temperature gradient (2007)
We report experimental observations of traveling waves in a pure fluid with a free surface situated in a long container submitted to a horizontal temperature gradient perpendicular to its large...
Ondes hydrothermales non-linéaires dans un disque et un anneau (2007)
Garnier, N., Chiffaudel, A., Daviaud, F., Prigent, A.
Nous nous intéressons à la convection thermocapillaire, produite par l'imposition d'un gradient {\it horizontal} de température sur une mince couche de fluide avec surface libre. En géométrie...
Ondes hydrothermales non-linéaires dans un disque et un anneau (2007)
Garnier, N., Chiffaudel, A., Daviaud, F., Prigent, A.
Nous nous intéressons à la convection thermocapillaire, produite par l'imposition d'un gradient {\it horizontal} de température sur une mince couche de fluide avec surface libre. En géométrie...
Magnetic induction in a turbulent flow of liquid sodium: mean behaviour and slow fluctuations (2007)
Ravelet, F., Volk, R., Chiffaudel, A., Daviaud, F., Dubrulle, B., Monchaux, R., ...
We study the flow response to an externally imposed homogeneous magnetic field in a turbulent swirling flow of liquid sodium -- the VKS2 experiment in which magnetic Reynolds numbers Rm up to 50 are...
Magnetic induction in a turbulent flow of liquid sodium: mean behaviour and slow fluctuations (2007)
Ravelet, F., Volk, R., Chiffaudel, A., Daviaud, F., Dubrulle, B., Monchaux, R., ...
We study the flow response to an externally imposed homogeneous magnetic field in a turbulent swirling flow of liquid sodium -- the VKS2 experiment in which magnetic Reynolds numbers Rm up to 50 are...
Petrelis, F., Bourgoin, M., Marie, L., Burguete, J., Chiffaudel, A., Daviaud, F., ...
We report the experimental observation of the alpha-effect. It consists in the generation of a current parallel to a magnetic field B0 applied to a turbulent swirling flow of liquid sodium. At low...
MHD in von Kármán swirling flows, development and first run of the sodium experiment (2007)
Marié, L., Burguete, J., Chiffaudel, A., Daviaud, F., Ericher, D., Gasquet, C., ...
We describe the motivations, development and first run of the Von Kármán Sodium (VKS) experiment built to study high Reynolds number magnetohydrodynamics and applications to the dynamo effect. The...
MHD in von Kármán swirling flows, development and first run of the sodium experiment (2007)
Marié, L., Burguete, J., Chiffaudel, A., Daviaud, F., Ericher, D., Gasquet, C., ...
We describe the motivations, development and first run of the Von Kármán Sodium (VKS) experiment built to study high Reynolds number magnetohydrodynamics and applications to the dynamo effect. The...
Generation of magnetic field by dynamo action in a turbulent flow of liquid sodium (2007)
Monchaux, R., Berhanu, M., Bourgoin, M., Moulin, M., Odier, Ph., Pinton, J. -F., ...
We report the observation of dynamo action in the VKS experiment, i.e., the generation of magnetic field by a strongly turbulent swirling flow of liquid sodium. Both mean and fluctuating parts of the...
Magnetic field reversals in an experimental turbulent dynamo (2007)
Berhanu, M., Monchaux, R., Fauve, S., Mordant, N., Petrelis, F., Chiffaudel, A., ...
We report the first experimental observation of reversals of a dynamo field generated in a laboratory experiment based on a turbulent flow of liquid sodium. The magnetic field randomly switches...
Transport of magnetic field by a turbulent flow of liquid sodium (2006)
Volk, R., Ravelet, F., Monchaux, R., Berhanu, M., Chiffaudel, A., Daviaud, F., ...
We study the effect of a turbulent flow of liquid sodium generated in the von K\'arm\'an geometry, on the localized field of a magnet placed close to the frontier of the flow. We observe that the...
On the properties of steady states in turbulent axisymmetric flows (2006)
Monchaux, R., Ravelet, F., Dubrulle, B., Chiffaudel, A., Daviaud, F.
We experimentally study the properties of mean and most probable velocity fields in a turbulent von K\'arm\'an flow. These fields are found to be described by two families of functions, as predicted...
Stefani, F., Xu, M., Gerbeth, G., Ravelet, F., Chiffaudel, A., Daviaud, F., ...
The intention of the ''von Karman sodium'' (VKS) experiment is to study the hydromagnetic dynamo effect in a highly turbulent and unconstrained flow. Much effort has been devoted to the optimization...
Numerical study of homogeneous dynamo based on experimental von Karman type flows (2003)
Marie, L., Burguete, J., Daviaud, F., Leorat, J.
A numerical study of the magnetic induction equation has been performed on von Karman type flows. These flows are generated by two co-axial counter-rotating propellers in cylindrical containers. Such...
Nonlinear magnetic induction by helical motion in a liquid sodium turbulent flow (2003)
Pétrelis, F., Bourgoin, M., Marié, L., Burguete, J., Chiffaudel, F., Daviaud, F., ...
We report an experimental study of the magnetic field ~BB induced by a turbulent swirling flow of liquid sodium submitted to a transverse magnetic field ~BB0. We show that the induced field can...
Numerical study of homogeneous dynamo based on experimental von Kármán type flows (2003)
Marié, L., Burguete, J., Daviaud, F., Léorat, J.
Abstract. A numerical study of the magnetic induction equation has been performed on von Kármán typeflows. These flows are generated by two co-axial counter-rotating propellers in cylindrical...
Petrelis, F., Bourgoin, M., Marie, L., Burguete, J., Chiffaudel, A., Daviaud, F., ...
We report the experimental observation of the alpha-effect. It consists in the generation of a current parallel to a magnetic field B0 applied to a turbulent swirling flow of liquid sodium. At low...
MHD measurements in the von Kármán sodium experiment (2002)
Bourgoin, M., Marié, L., Pétrélis, F., Gasquet, C., Guigon, A., Luciani, J.B., ...
We study the magnetic induction in a confined swirling flow of liquid sodium, at integral magnetic Reynolds numbers up to 50. More precisely, we measure in situ the magnetic field induced by the flow...
Open questions about homogeneous fluid dynamos: the VKS experiments (2002)
Marié, L., Pétrélis, F., Bourgoin, M., Burguete, J., Chiffaudel, A., Daviaud, F., ...
We consider several problems that arise in the context of homogeneous fluid dynamos such as the e ect of turbulence on the dynamo threshold, the saturation level of the generated magnetic eld above...
A powerful local shear instability in stratified disks (2001)
Richard, D., Hersant, F., Dauchot, O., Daviaud, F., Dubrulle, B., Zahn, J-P.
In this paper, we show that astrophysical accretion disks are dynamically unstable to non-axisymmetric disturbances. This instability is present in any stably stratified anticyclonically sheared flow...
Multi-scale clustering in granular surface flows (2001)
Bonamy, D., Daviaud, F., Laurent, L., Bonetti, M., Bouchaud, J. P.
We investigate steady granular surface flows in a rotating drum and demonstrate the existence of rigid clusters of grains embedded in the flowing layer. These clusters are fractal and their size is...
Experimental study of granular surface flows via a fast camera: a continuous description (2001)
Bonamy, D., Daviaud, F., Laurent, L.
Depth averaged conservation equations are written for granular surface flows. Their application to the study of steady surface flows in a rotating drum allows to find experimentally the constitutive...
"Barchan" dunes in the lab (2001)
Dauchot, O., Lechenault, F., Gasquet, C., Daviaud, F.
We demonstrate the feasibility of studying dunes in a laboratory experiment. It is shown that an initial sand pile, under a wind flow carrying sand, flattens and gets a shape recalling barchan dunes....
Burguete, J., Mukolobwiez, N., Daviaud, F., Garnier, N., Chiffaudel, A.
We report experiments on buoyant-thermocapillary instabilities in differentially heated liquid layers. The results are obtained for a fluid of Prandtl number 10 in a rectangular geometry with...
Electrical conductance of a 2D packing of metallic beads under thermal perturbation (2000)
Bonamy, D., Laurent, L., Claudin, Ph., Bouchaud, J. -Ph, Daviaud, F.
Electrical conductivity measurements on a 2D packing of metallic beads have been performed to study internal rearrangements in weakly pertubed granular materials. Small thermal perturbations lead to...
Bekki-Nozaki Amplitude Holes in Hidrothermal Nonlinear Waves (1999)
Burguete, J., Chaté, H., Daviaud, F., Mukolobwiez, N.
We present and analyze experimental results on the dynamics of hydrothermal waves occurring in a laterally heated fluid layer. We argue that the large-scale modulations of the waves are governed by a...
Origin of waves in surface-tension-driven convection (1997)
Garcimartín, A., Mukolobwiez, N., Daviaud, F.
Waves appear in a liquid layer with a free surface if a sufficiently high horizontal temperature gradient is imposed. These waves have been compared to the hydrothermal waves predicted by a linear...
Traveling waves in a fluid layer submitted to a horizontal temperature gradient (1993)
We report experimental observations of traveling waves in a pure fluid with a free surface situated in a long container submitted to a horizontal temperature gradient perpendicular to its large...
OSCILLATING INSTABILITY IN ONE-DIMENSIONAL RAYLEIGH-BENARD CONVECTION (1989)
Daviaud, F., Berge, P., Dubois, M.
Collective periodic oscillations of the rolls' position are observed in experiments of Rayleigh-Bénard convection, when one of the horizontal extensions is smaller than the depth of the fluid layer...
OSCILLATING INSTABILITY IN ONE-DIMENSIONAL RAYLEIGH-BENARD CONVECTION (1989)
Daviaud, F., Berge, P., Dubois, M.
Collective periodic oscillations of the rolls' position are observed in experiments of Rayleigh-Bénard convection, when one of the horizontal extensions is smaller than the depth of the fluid layer...
OSCILLATING INSTABILITY IN ONE-DIMENSIONAL RAYLEIGH-BENARD CONVECTION (1989)
Daviaud, F., Berge, P., Dubois, M.
Collective periodic oscillations of the rolls' position are observed in experiments of Rayleigh-Bénard convection, when one of the horizontal extensions is smaller than the depth of the fluid layer...