Convection driven by internal heating

David Goluskin; Edward A. Spiegel

doi:10.1016/j.physleta.2012.10.037

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arXiv · 1210.8154

Convection driven by internal heating

David Goluskin·Edward A. Spiegel

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Abstract

Two-dimensional direct numerical simulations are conducted for convection sustained by uniform internal heating in a horizontal fluid layer. Top and bottom boundary temperatures are fixed and equal. Prandtl numbers range from 0.01 to 100, and Rayleigh numbers (R) are up to 5x10^5 times the critical R at the onset of convection. The asymmetry between upward and downward heat fluxes is non-monotonic in R. In a broad high-R regime, dimensionless mean temperature scales as R^{-1/5}. We discuss the scaling of mean temperature and heat-flux-asymmetry, which we argue are better diagnostic quantities than the conventionally used top and bottom Nusselt numbers.

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David Goluskin, Edward A. Spiegel. 2012-10-30. Convection driven by internal heating. https://doi.org/10.1016/j.physleta.2012.10.037

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