Key points are not available for this paper at this time.
In a low temperature He gas Rayleigh-B\'enard experiment, Rayleigh numbers from 10^3 to more than 10^14 are explored. Local velocity is estimated through the time lag between two closeby temperature probes. This allows characterizing of the high Rayleigh regime (Ra>10^11) as a fully turbulent one, possibly corresponding to the asymptotic regime predicted by R. Kraichnan Phys. Fluids 5, 1374 (1962).
Chavanne et al. (Mon,) studied this question.