Scaling laws in axisymmetric magnetohydrodynamic duct flows

Abstract

We report on a numerical study of axisymmetric flow of liquid metal in a circular duct with rectangular cross-section. The flow is forced through the combination of an axial magnetic field and a radial current. Sweeping a wide range of forcing parameters, we identify the different regimes which characterize the flows and explicit the associate scaling laws. Experimental results are interpreted in the light of our numerical simulations.

Turbulence in electromagnetically driven Keplerian flows

“…A similar regime seems to have been observed in at least one previous experiments (Baylis 1971) and one recent numerical study (Poye et al. 2020). As shown by figure 3, this regime is observed for and mT.…”

“…Although the scaling law (4.4) shares some similarities with the one found by Poye et al. (2020), our full expression is quite different, and leads to values one order of magnitude smaller. This is due to some differences between our experiment and the set-up studied by these authors, in particular the relatively large aspect ratio used here () and the fact that in the KEPLER experiment.…”

Numerical simulations of swirling electrovortex flows in cylinders

“…We also know that it exists as an intermediate regime in duct flows (Poyé et al. 2020; Vernet et al. 2021).…”

A critical transition of two-dimensional flow in toroidal geometry

“…Most fluid mechanics studies in toroidal geometry have focused on liquid metal flows (Baylis & Hunt 1971), and very few studies consider the axisymmetric limit (Poyé et al. 2020). We think that, even if the transition that we will assess is shown in a too simple set-up to claim a one-to-one correspondence with the LH-transition, it does illustrate the robustness of the 2D3C to 2-D two-component (2D2C) transition in toroidal geometry, and its ability to dramatically change the flow physics and self-organization properties of the flow.…”