Abstract
The most fundamental difficulty in the construction of an Earth-like dynamo model is associated with the constraint caused by the rapid rotation of the Earth. To stabilise numerical codes, many workers have introduced hyperviscosity into the governing equations. One of the major effects introduced by hyperviscosity is to offset the rotational constraint, and, consequently, to alter the key dynamics of an Earth-like dynamo. In this paper, an Earth-like convection model with or without the presence of an imposed magnetic field is investigated with or without the effect of hyperviscosity. A nonlinear dynamo model with the mean field approximation is also used to examine the dynamical effect of hyperviscosity. The results suggest that great care should be taken when hyperviscosity is employed in geodynamo models.
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Zhang, K., Jones, C.A. & Sarson, G.R. The Dynamical Effects of Hyperviscosity on Numerical Geodynamo Models. Studia Geophysica et Geodaetica 42, 247–253 (1998). https://doi.org/10.1023/A:1023336216088
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DOI: https://doi.org/10.1023/A:1023336216088