Generalized action invariants for drift waves-zonal flow systems

  title={Generalized action invariants for drift waves-zonal flow systems},
  author={Andrei I. Smolyakov and Patrick H. Diamond},
  journal={Physics of Plasmas},
Generalized action invariants are identified for various models of drift wave turbulence in the presence of the mean shear flow. It is shown that the wave kinetic equation describing the interaction of the small scale turbulence and large scale shear flow can be naturally writen in terms of these invariants. Unlike the wave energy, which is conserved as a sum of small- and large-scale components, the generalized action invariant is shown to correspond to a quantity which is conserved for the… 

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