On the role of the Prandtl number in convection driven by heat sources and sinks

@article{Miquel2020OnTR,
  title={On the role of the Prandtl number in convection driven by heat sources and sinks},
  author={Benjamin Miquel and Vincent Bouillaut and S'ebastien Aumaitre and Basile Gallet},
  journal={Journal of Fluid Mechanics},
  year={2020},
  volume={900}
}
Abstract We report on a numerical study of turbulent convection driven by a combination of internal heat sources and sinks. Motivated by a recent experimental realisation (Lepot etal., Proc. Natl Acad. Sci. USA, vol. 115 (36), 2018, pp. 8937–8941), we focus on the situation where the cooling is uniform, while the internal heating is localised near the bottom boundary, over approximately one tenth of the domain height. We obtain scaling laws ${Nu} \sim {Ra} ^{\gamma } {Pr}^{\chi }$ for the heat… 
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Turbulence deep within the interior of stars bears many qualitative similarities with turbulence in the ocean and atmosphere on Earth. In both contexts, various forms of convective instabilities and
Velocity-informed upper bounds on the convective heat transport induced by internal heat sources and sinks
Three-dimensional convection driven by internal heat sources and sinks (CISS) leads to experimental and numerical scaling laws compatible with a mixing-length—or ‘ultimate’—scaling regime Nu∼Ra.
Experimental observation of the geostrophic turbulence regime of rapidly rotating convection
TLDR
Heat transport measurements in quantitative agreement with the fully turbulent regime of rotating convection are reported, pointing to an unexpected sensitivity of the heat transport efficiency to the precise distribution of heat sources and sinks, which greatly varies from planets to stars.
Coral: a parallel spectral solver for fluid dynamics and partial differential equations
  • B. Miquel
  • Computer Science
    J. Open Source Softw.
  • 2021
Coral is a fast, flexible, and efficient time-stepper for solving a large class of partial differential equations, at the core of which are the Navier-Stokes equations that govern fluid motions.

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