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arXiv · 2201.08513

Chiral Pattern in Nonrotating Spherical Convection

Akira Kageyama·Nobuaki Ohno
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Abstract

When the Rayleigh number is low, Rayleigh-B\'enard convection in a nonrotating spherical shell with central gravity has symmetric solutions in terms of three-dimensional discrete rotation. All the known patterns with the regular polyhedral symmetries accompany reflection symmetry. We found a new type of steady convection in a nonrotating spherical shell by computer simulations. The pattern has the discrete rotational symmetry of a regular tetrahedron with no reflection symmetry. The convection consists of six pairs of spiral rolls placed on 12 faces of a spherical dodecahedron. Depending on the winding of the spirals, there are two possible configurations that are mirror images of one another.

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Akira Kageyama, Nobuaki Ohno. 2022-01-21. Chiral Pattern in Nonrotating Spherical Convection. https://arxiv.org/abs/2201.08513

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