Noise/Chaos Distinction Applied to the Study of a Fluidized Bed

The observation of chaos in fluidization have been claimed by some authors. We analyze the dynamics of a gas-solid fluidized bed and demonstrate that the dynamics is not chaotic but noisy. The random process is studied by using the Hurst analysis in order to look for long-term correlations in the signals. The dynamics may then be modelled by a fractal Brownian motion process