Geometry-induced self-excited dynamo in a regular tetrahedron
Abstract
We present a rotation-free magnetohydrodynamic dynamo driven by laminar thermal convection in a regular tetrahedral cavity. The tetrahedral boundaries organize the convective flow into a robust pattern of helical convection cells without global rotation or turbulence. Direct numerical simulations demonstrate exponential amplification of a weak seed magnetic field followed by nonlinear saturation. In the reference calculation, the saturated magnetic energy exceeds the kinetic energy. The velocity field develops D4 dihedral symmetry, while the self-generated magnetic field exhibits a corresponding signed D4 symmetry, including antisymmetry under π rotations about the two horizontal axes. Analysis of the velocity and magnetic-field structures reveals a closed induction cycle sustained by geometry-induced helical convection. This system provides a conceptually simple setting for isolating and understanding the fundamental physical processes underlying magnetohydrodynamic dynamo action.
Related
- Collisionless dynamo seeds from phase mixing-induced electron slippage
- Hyperfine-induced lifetime extension of nuclear excited states
- Excited-state-induced nonlinearity and polarity reversals in the thermocurrent through a quantum dot
- From breakfast, lunch, and dinner to the Bell-inequality tetrahedron
- Optimal Interferometer Geometry for Gravitationally Induced Quantum Entanglement
BibTeX
@misc{kageyama2026geometryinduced,
title = {{Geometry-induced self-excited dynamo in a regular tetrahedron}},
author = {Akira Kageyama},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2606.11781},
eprint = {2606.11781},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2606.11781},
}
RIS
TY - UNPB
TI - Geometry-induced self-excited dynamo in a regular tetrahedron
AU - Akira Kageyama
PY - 2026
DA - 2026/10/02
PB - arXiv
DO - 10.48550/arxiv.2606.11781
UR - https://arxiv.org/abs/2606.11781
AB - We present a rotation-free magnetohydrodynamic dynamo driven by laminar thermal convection in a regular tetrahedral cavity. The tetrahedral boundaries organize the convective flow into a robust pattern of helical convection cells without global rotation or turbulence. Direct numerical simulations demonstrate exponential amplification of a weak seed magnetic field followed by nonlinear saturation. In the reference calculation, the saturated magnetic energy exceeds the kinetic energy. The velocity field develops D_4 dihedral symmetry, while the self-generated magnetic field exhibits a corresponding signed D_4 symmetry, including antisymmetry under π rotations about the two horizontal axes. Analysis of the velocity and magnetic-field structures reveals a closed induction cycle sustained by geometry-induced helical convection. This system provides a conceptually simple setting for isolating and understanding the fundamental physical processes underlying magnetohydrodynamic dynamo action.
ER -