External Noise and the Onset of Turbulent Convection

The effect of fluctuations on the transition to turbulence is examined by introducing large-amplitude noise into the boundary temperature of a Rayleigh-Bénard system. The response can be largely described in terms of variables whose induced fluctuations are much slower than either the natural oscillations or the external noise. However, the sequence of transitional regimes and the statistical properties of the turbulent state are not dramatically affected.