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Diffusion-Free Scaling in Rotating Spherical Rayleigh-Benard Convection.

ABSTRACT: Direct numerical simulations are employed to reveal three distinctly different flow regions in rotating spherical Rayleigh-Bénard convection. In the high-latitude region I vertical (parallel to the axis of rotation) convective columns are generated between the hot inner and the cold outer sphere. The mid-latitude region II is dominated by vertically aligned convective columns formed between the Northern and Southern hemispheres of the outer sphere. The diffusion-free scaling, which indicates bulk-dominated convection, originates from this mid-latitude region. In the equator region III , the vortices are affected by the outer spherical boundary and are much shorter than in region II .

SUBMITTER: Wang G

PROVIDER: S-EPMC9285093 | biostudies-literature | 2021 Oct

REPOSITORIES: biostudies-literature

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Diffusion-Free Scaling in Rotating Spherical Rayleigh-Bénard Convection.

Wang Guiquan G Santelli Luca L Lohse Detlef D Verzicco Roberto R Stevens Richard J A M RJAM

Geophysical research letters 20211021 20

Direct numerical simulations are employed to reveal three distinctly different flow regions in rotating spherical Rayleigh-Bénard convection. In the high-latitude region I vertical (parallel to the axis of rotation) convective columns are generated between the hot inner and the cold outer sphere. The mid-latitude region I I is dominated by vertically aligned convective columns formed between the Northern and Southern hemispheres of the outer sphere. The diffusion-free scaling, which indicates bu ...[more]

PMID: 35844630

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