A numerical approach for transient magnetohydrodynamic flows

TL;DR

This paper introduces a numerical method for modeling laminar-turbulent transition in magnetohydrodynamic flows at low magnetic Reynolds numbers, using perturbation-based solvers within the Nectar++ framework.

Contribution

It presents a novel numerical approach incorporating local disturbances to trigger flow transition, with applications to Hartmann flow and flow in bends.

Findings

The method effectively models flow stability and transition.

Local disturbances can trigger laminar-turbulent transition.

The approach is validated on Hartmann flow and bend flow examples.

Abstract

In the article the authors present a numerical method for modelling a laminar-turbulent transition in magnetohydrodynamic flows. The equations in the small magnetic Reynolds numbers approach is considered. Speed, pressure and electrical potential are decomposed to the sum of the state values and the finite amplitude perturbations. A solver based on the Nectar++ framework is described. The authors suggest to use of small-length local disturbances as a transition trigger. They can be imposed by blowing or electrical enforcing. The stability of the Hartmann flow and the flow in the bend are considered as examples.