A Liquid Sodium Plume-Driven Helicity Dynamo Experiment

New Mexico Institute Of Mining And Technology, Socorro NM

Investigators

Abstract

The Liquid Sodium Dynamo Experiment at New Mexico Tech is designed to demonstrate how naturally occurring flows in planets, stars, and Active Galactic Nuclei (AGN) accretion disks can generate the magnetic fields of these bodies. The scientific question of the research is whether driven plumes, necessary for coherent helicity generation in a conducting fluid will create so much turbulent resistivity as to prevent the necessary orthogonal omega or shear gain and thus prevent exponential dynamo gain. Educationally, the project offers research opportunities for undergraduates. The standard belief is that turbulence in a conducting fluid will make a dynamo in astrophysical circumstances regardless of the randomness of the motions. This experiment is designed to prove the contrary. A low turbulent shear flow in liquid sodium (this experiment) has already demonstrated an omega gain of a factor of eight. The experimental question is whether helicity injection of approximately one-eighth the shear flow can recreate the original poloidal field without reducing the omega gain by turbulent resistivity below threshold.