Ultimate state of thermal convection

Phys Rev Lett. 2003 Jan 24;90(3):034502. doi: 10.1103/PhysRevLett.90.034502. Epub 2003 Jan 24.


The ultimate regime of thermal convection, the so-called Kraichnan regime [R. H. Kraichnan, Phys. Fluids 5, 1374 (1962)]], hitherto has been elusive. Here numerical evidence for that regime is presented by performing simulations of the bulk of turbulence only, eliminating the thermal and kinetic boundary layers and replacing them with periodic boundary conditions.