Power spectra of nonlinearly coupled waves

Swinney et al. (1977) have found that turbulence in rotational Couette flow results from a small number of instabilities. They have raised the question of whether these instabilities conform with the ideas of Ruelle and Takens (1971). We show that a simple model of the Couette flow yields power spectra similar to those seen in the experiments. The model is consistent with the Ruelle and Takens picture.