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arXiv · 2101.04160

Wave-kinetic approach to zonal-flow dynamics: recent advances

Hongxuan Zhu·I. Y. Dodin
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Abstract

Basic physics of drift-wave turbulence and zonal flows has long been studied within the framework of wave-kinetic theory. Recently, this framework has been re-examined from first principles, which has led to more accurate yet still tractable "improved" wave-kinetic equations. In particular, these equations reveal an important effect of the zonal-flow "curvature" (the second radial derivative of the flow velocity) on dynamics and stability of drift waves and zonal flows. We overview these recent findings and present a consolidated high-level picture of (mostly quasilinear) zonal-flow physics within reduced models of drift-wave turbulence.

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Hongxuan Zhu, I. Y. Dodin. 2021-01-11. Wave-kinetic approach to zonal-flow dynamics: recent advances. https://doi.org/10.1063/5.0043784

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