Fludyco Task 1: the fluid dynamics of core formation. ERC Consolidator Project FLUDYCO 2018-10-31 | The FLUDYCO project is a research project in geophysical fluid dynamics. It aims at a better understanding of the flows in planetary cores from their formation to their current dynamics. The project takes place at IRPHE in Marseille, France. It has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme.In this task 1, we address the fluid dynamics of iron fragmentation during the later stages of planetary accretion, in order to produce innovative, dynamically reliable models of planet formation.
Internal waves generation by turbulent convection in a spherical shell ERC Consolidator Project FLUDYCO 2020-10-07 | Radial velocity in the convective region (bottom half of the spherical shell) and in the stably stratified layer above (top half). The velocity has been amplified by a factor ~40 in the stratified region, for a better visualization.
Fludyco Task 2: the fluid dynamics of heterogeneous core convection. ERC Consolidator Project FLUDYCO 2018-10-30 | The FLUDYCO project is a research project in geophysical fluid dynamics. It aims at a better understanding of the flows in planetary cores from their formation to their current dynamics. The project takes place at IRPHE in Marseille, France. It has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme.In this task 2, we investigate the flows driven in a stratified layer at the top of a liquid core and their influence on the global convective dynamics and related dynamo.
ERC project Fluid Dynamics of Planetary Cores (Fludyco) ERC Consolidator Project FLUDYCO 2018-10-30 | The FLUDYCO project is a research project in geophysical fluid dynamics. It aims at a better understanding of the flows in planetary cores from their formation to their current dynamics. The project takes place at IRPHE in Marseille, France. It has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme.
Fludyco Task 3: the fluid dynamics of core rotation. ERC Consolidator Project FLUDYCO 2018-10-30 | The FLUDYCO project is a research project in geophysical fluid dynamics. It aims at a better understanding of the flows in planetary cores from their formation to their current dynamics. The project takes place at IRPHE in Marseille, France. It has received funding from the European Research Council (ERC) under the European Union’s Horizon 2020 research and innovation programme.In this task 3, building upon the recent emergence of alternative models for core dynamics, we quantitatively examine the non-linear saturation and turbulent state of the flows driven by libration, as well as the shape and intensity of the corresponding dynamo.
Internal Wave Generation by Turbulent Convection ERC Consolidator Project FLUDYCO 2018-09-12 | 2D cuts of a 3D simulation of internal waves (z \ge 1) generated by turbulent convection (z \le 1): vertical slices at y=0 of (a) vertical velocity, (b) temperature gradient (minus the horizontal mean); horizontal slices of vertical velocity at (c) z=0.7, (d) z=1.3. Variables shown in the wave region in (a) and (b) have been multiplied by 10000, 1000, respectively. The physical model solved numerically is a self-consistent model of convective--stably-stratified fluids; see doi.org/10.1103/PhysRevFluids.2.094804 for more details. Reference: doi.org/10.1017/jfm.2018.669
Mechanical forcings in Nature and in the lab ERC Consolidator Project FLUDYCO 2018-06-19 | Gravitational interactions between planets give rise to so-called libration motions, precession motions and tides. Generically called mechanical forcings, they excite fully turbulent flows in planetary cores that we study in the lab thanks to dedicated set-ups.
Turbulently-generated internal waves ERC Consolidator Project FLUDYCO 2018-06-14 | Direct numerical simulation results showing the vertical velocity field w in a mixed convective--stably-stratified fluid. Vertical velocity patterns show convective motions in the lower part of the domain (z \lt 0.67) and internal-wave motions in the upper part (z \geq 0.67) [z=0.67 shown by the dashed horizontal line]. Note that energy propagates upward along wave crests, so crests toward the upper left (right) correspond to retrograde (prograde) waves. The internal waves in the stable region drive a large-scale horizontal flow in the stable zone, similar to oscillations of equatorial winds in Earth's stratosphere, which is a phenomenon known as the Quasi-Biennial Oscillation.
Oscillating wind driven by turbulently-generated internal waves (high frame rate) ERC Consolidator Project FLUDYCO 2018-06-12 | Direct numerical simulation results showing the vertical velocity field w in a mixed convective--stably-stratified fluid. Vertical velocity patterns show convective motions in the lower part of the domain (z \lt 0.67) and internal-wave motions in the upper part (z \geq 0.67) [z=0.67 shown by the dashed horizontal line]. Note that energy propagates upward along wave crests, so crests toward the upper left (right) correspond to retrograde (prograde) waves. The solid black line in the wave region (z \geq 0.67) shows the horizontal mean flow U (with U=0 corresponding to x=1). The mean flow can be seen to change direction periodically and is driven by the internal waves in the stable region, much like internal waves drive oscillations of equatorial winds in Earth's stratosphere, which is a phenomenon known as the Quasi-Biennial Oscillation.
Libration experiment at IRPHE ERC Consolidator Project FLUDYCO 2018-01-03 | This is a setup mimicking librations of a planet deformed by tidal force. Our planet is a 50 cm-wide ellipsoidal container mounted on a rotating table (because planets rotate) and on an oscillating motor going back and forth to periodically increase and decrease the rotation rate of the planet. As a result, you can see the rotation of the container alternatively going faster and slower.
Mixed convective stably-stratified dynamics at the initial time [vorticity] ERC Consolidator Project FLUDYCO 2017-06-07 | Time evolution of the vorticity field \omega starting from the conductive state. The physical parameters are Pr=1, Ra=8*10^7, S=1. The top and bottom boundaries are no slip. Time and vorticity are normalized by the turnover time \tau_c=1/f_c=2\pi/\sqrt{Pr*Ra}.
Mixed convective stably-stratified dynamics at thermal equilibrium [stiff] ERC Consolidator Project FLUDYCO 2017-06-07 | Classical convective regime with a strongly stably-stratified layer above shown by the time evolution of the density field (lower layer) and vorticity field \omega (upper layer) at thermal equilibrium, i.e. after several thousands convective turnover times. The physical parameters are Pr=1, Ra=8*10^7, S=2^8. The interface between the convective and wave dynamics is stiff. The top and bottom boundaries are no slip and isothermal. Time and vorticity are normalized by the turnover time \tau_c=1/f_c=2\pi/\sqrt{Pr*Ra}.
Mixed convective stably-stratified dynamics at thermal equilibrium [very flexible] ERC Consolidator Project FLUDYCO 2017-06-07 | Entrainment regime (convection is dominated by fluid parcels supposed to be stable) shown by the time evolution of the density field (lower layer) and vorticity field \omega (upper layer) at thermal equilibrium, i.e. after several thousands convective turnover times. The physical parameters are Pr=1, Ra=8*10^7, S=2^-8. The top and bottom boundaries are no slip and isothermal. Time and vorticity are normalized by the turnover time \tau_c=1/f_c=2\pi/\sqrt{Pr*Ra}.
Mixed convective stably-stratified dynamics at thermal equilibrium [flexible] ERC Consolidator Project FLUDYCO 2017-06-07 | Convective regime strongly affected by the upper stable layer above shown by the time evolution of the density field (lower layer) and vorticity field \omega (upper layer) at thermal equilibrium, i.e. after several thousands convective turnover times. The physical parameters are Pr=1, Ra=8*10^7, S=2^0. The interface between the convective and wave dynamics is flexible. The top and bottom boundaries are no slip and isothermal. Time and vorticity are normalized by the turnover time \tau_c=1/f_c=2\pi/\sqrt{Pr*Ra}.
Mixed convective stably-stratified dynamics at the initial time [T] ERC Consolidator Project FLUDYCO 2017-05-23 | Time evolution of the temperature field T starting from the conductive state. The physical parameters are Pr=1, Ra=8*10^7, S=1. The temperature at the top and bottom boundaries are set to -20 and 1, respectively. Time is normalized by the turnover time \tau_c=2\pi/\sqrt{Pr*Ra}.
BL Temperature colormap for Ra1=1e8, r=1/64 (S~0.3) ERC Consolidator Project FLUDYCO 2016-11-10 | The fluid is stable for T less than 0, and the bottom heated plate is at T=1. We focus on the plume ejection mechanism close to the plate.Although the fluid is stably stratified close to the bottom BL, plumes can be seen to detach where the local Rayleigh number is Ra=1101 within the unstable BL. Where Ra=1101 but T less than 0, no plumes are ejected.
The true dynamics of the iron rain... ERC Consolidator Project FLUDYCO 2016-09-28 | Sedimentation and fragmentation of a blob of liquid metal in a viscous ambient fluid (vertical size 70cm / slowed down 33 times). This is a laboratory model of the core formation during planetary accretion. (copyright JB Wacheul, Fludyco, IRPHE)
