Towards the ultimate regime in Rayleigh-Benard turbulence
- Olga Shishkina (MPI for Dynamics and Self-Organization, Göttingen)
Abstract
Rayleigh-Benard convection - a fluid motion in a layer heated from below and cooled from above - is one of the paradigmatic systems in fluid dynamics. The key question here is how does the heat transport (Nusselt number Nu) depend on the thermal driving strength (Rayleigh number Ra) for extremely large Ra (in the ultimate regime, relevant in geophysical and astrophysical applications)?
We will discuss the existing physical models for the ultimate regime and their relation to the mathematically rigorous upper bounds for the heat transport.
The talk is based on papers by D. Lohse and O. Shishkina, ``Ultimate Rayleigh-Benard turbulence'' (to appear in Reviews of Modern Physics) and ``Ultimate turbulent thermal convection'' Physics Today 76 (2023).