Turbulent Cells in Stars: Fluctuations in Kinetic Energy and Luminosity

@article{Arnett2010TurbulentCI,
  title={Turbulent Cells in Stars: Fluctuations in Kinetic Energy and Luminosity},
  author={W. David Arnett and Casey a. Meakin},
  journal={The Astrophysical Journal},
  year={2010},
  volume={741},
  pages={33}
}
Three-dimensional (3D) hydrodynamic simulations of shell oxygen burning exhibit bursty, recurrent fluctuations in turbulent kinetic energy. These are shown to be due to a general instability of the convective cell, requiring only a localized source of heating or cooling. Such fluctuations are shown to be suppressed in simulations of stellar evolution which use the mixing-length theory. Quantitatively similar behavior occurs in the model of a convective roll (cell) of Lorenz, which is known to… Expand
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