The standard magnetorotational instability (SMRI) is a promising mechanism for turbulence and rapid accretion in astrophysical disks. It is a magnetohydrodynamic (MHD) instability that destabilizes otherwise hydrodynamically stable disk flow. Due to its microscopic nature at astronomical distances and stringent requirements in laboratory experiments, SMRI has remained unconfirmed since its proposal, despite its astrophysical importance. Here we report a nonaxisymmetric MHD instability in a modified Taylor-Couette experiment. To search for SMRI, a uniform magnetic field is imposed along the rotation axis of a swirling liquid-metal flow. The instability initially grows exponentially, becoming prominent only for sufficient flow shear and moderate magnetic field. These conditions for instability are qualitatively consistent with SMRI, but at magnetic Reynolds numbers below the predictions of linear analyses with periodic axial boundaries. Three-dimensional numerical simulations, however, reproduce the observed instability, indicating that it grows linearly from the primary axisymmetric flow modified by the applied magnetic field.
Wang, Yin, et al. "Identification of a non-axisymmetric mode in laboratory experiments searching for standard magnetorotational instability." Nature Communications, vol. 13, no. 1, Aug. 2022. https://doi.org/10.1038/s41467-022-32278-0
Wang, Yin, Gilson, Erik P., Ebrahimi, Fatima, Goodman, Jeremy, Caspary, Kyle J., Winarto, Himawan W., & Ji, Hantao (2022). Identification of a non-axisymmetric mode in laboratory experiments searching for standard magnetorotational instability. Nature Communications, 13(1). https://doi.org/10.1038/s41467-022-32278-0
Wang, Yin, Gilson, Erik P., Ebrahimi, Fatima, et al., "Identification of a non-axisymmetric mode in laboratory experiments searching for standard magnetorotational instability," Nature Communications 13, no. 1 (2022), https://doi.org/10.1038/s41467-022-32278-0
@article{osti_1880388,
author = {Wang, Yin and Gilson, Erik P. and Ebrahimi, Fatima and Goodman, Jeremy and Caspary, Kyle J. and Winarto, Himawan W. and Ji, Hantao},
title = {Identification of a non-axisymmetric mode in laboratory experiments searching for standard magnetorotational instability},
annote = {Abstract The standard magnetorotational instability (SMRI) is a promising mechanism for turbulence and rapid accretion in astrophysical disks. It is a magnetohydrodynamic (MHD) instability that destabilizes otherwise hydrodynamically stable disk flow. Due to its microscopic nature at astronomical distances and stringent requirements in laboratory experiments, SMRI has remained unconfirmed since its proposal, despite its astrophysical importance. Here we report a nonaxisymmetric MHD instability in a modified Taylor-Couette experiment. To search for SMRI, a uniform magnetic field is imposed along the rotation axis of a swirling liquid-metal flow. The instability initially grows exponentially, becoming prominent only for sufficient flow shear and moderate magnetic field. These conditions for instability are qualitatively consistent with SMRI, but at magnetic Reynolds numbers below the predictions of linear analyses with periodic axial boundaries. Three-dimensional numerical simulations, however, reproduce the observed instability, indicating that it grows linearly from the primary axisymmetric flow modified by the applied magnetic field.},
doi = {10.1038/s41467-022-32278-0},
url = {https://www.osti.gov/biblio/1880388},
journal = {Nature Communications},
issn = {ISSN 2041-1723},
number = {1},
volume = {13},
place = {United Kingdom},
publisher = {Nature Publishing Group},
year = {2022},
month = {08}}
Proceedings of the Royal Society of London. Series A, Containing Papers of a Mathematical and Physical Character, Vol. 93, Issue 648, p. 148-154https://doi.org/10.1098/rspa.1917.0010