Critical Dynamics near the Oscillatory Instability in Rayleigh-Bénard Convection

Abstract
The oscillatory temperature amplitude of a low-Prandtl-number fluid in Rayleigh-Bénard convection is shown to exhibit critical slowing down near the onset of oscillatory convection. The data are analyzed in the context of a mean-field Landau-Hopf equation. We find the magnitude of the power-law exponent for the dynamic relaxation to be 1.01±0.02 and 1.00±0.02 above and below onset, respectively, in agreement with the theoretical predictions.