Renormalized expression for the turbulent energy dissipation rate.

نویسندگان

  • C Johnston
  • W D McComb
چکیده

Conditional elimination of degrees of freedom is shown to lead to an exact expression for the rate of turbulent energy dissipation in terms of a renormalized viscosity and a correction. The correction is neglected on the basis of a previous hypothesis [W. D. McComb and C. Johnston, J. Phys. A 33, L15 (2000)] that there is a range of parameters for which a quasistochastic estimate is a good approximation to the exact conditional average. This hypothesis was tested by a perturbative calculation to second order in the local Reynolds number, and the Kolmogorov prefactor (taken as a measure of the renormalized dissipation rate) was found to reach a fixed point which was insensitive to initial values of the kinematic viscosity and to values of the spatial rescaling factor h in the range 0.4< or =h< or =0.8.

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عنوان ژورنال:
  • Physical review. E, Statistical, nonlinear, and soft matter physics

دوره 63 1 Pt 2  شماره 

صفحات  -

تاریخ انتشار 2001