Refraction and reflection patterns of an inclined turbulent conductive jet induced by a local transverse magnetic field

Abstract

This study investigates the interaction between turbulent conductive jets and transverse magnetic fields, focusing on the effects of jet inclination angle and magnetic field strength. This phenomenon is relevant to both metallurgy and astrophysics. In metallurgy, complex localized magnetic fields are frequently used to control molten metal flows. Similarly, in astrophysics, a comparable effect occurs with relativistic jets (RJs) emitted by active galactic nuclei (AGN), where these jets can be deflected or refracted when encountering magnetic fields. In this study, it was observed that the jet undergoes refraction, meaning its initial direction changes when passing through a direct current (DC) magnetic field. This refraction is accompanied by expansion and fluctuations in the jet's mean flow. The degree of refraction was measured using a refractive index (RI), denoted as $n$, which was related to the Stuart (magnetic interaction) number $N$. For moderate Stuart numbers ($N\le 0.5$), the refraction index followed a simple relationship, $n\approx 1-N$, regardless of the jet's inclination angle. At higher values ($N>0.5$), refraction index varies with inclination due to the development of reverse flow zones adjacent to the main jet, a behavior previously reported by the authors. At certain critical $N$ values, full reflection occurs, where the jet cannot penetrate the magnetic field. When the jet is confined by conductive walls, refraction intensifies, leading to earlier full reflection. These findings provide insight into the mechanisms behind the bending and expansion of astrophysical relativistic jets, suggesting that similar magnetic interactions may influence the RJs behavior as they encounter magnetic fields in space.