Kármán–Howarth Theorem for the Lagrangian averaged Navier-Stokes alpha model
نویسنده
چکیده
The Kármán–Howarth theorem is derived for the Lagrangian averaged Navier-Stokes alpha (LANS−α) model of turbulence. Thus, the LANS−α model’s preservation of the fundamental transport structure of the Navier-Stokes equations also includes preservation of the transport relations for the velocity autocorrelation functions. This result implies that the alpha-filtering in the LANS−α model of turbulence does not suppress the intermittency of its solutions at separation distances large compared to alpha.
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