Turbulent convection: comparing the moment equations to numerical simulations

F. Kupka

doi:10.1086/312363

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arXiv · astro-ph/9909331

Turbulent convection: comparing the moment equations to numerical simulations

F. Kupka

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Abstract

The non-local hydrodynamic moment equations for compressible convection are compared to numerical simulations. Convective and radiative flux typically deviate less than 20% from the 3D simulations, while mean thermodynamic quantities are accurate to at least 2% for the cases we have investigated. The moment equations are solved in minutes rather than days on standard workstations. We conclude that this convection model has the potential to considerably improve the modelling of convection zones in stellar envelopes and cores, in particular of A and F stars.

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F. Kupka. 1999-09-20. Turbulent convection: comparing the moment equations to numerical simulations. https://doi.org/10.1086/312363

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