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Derivative moments in stationary homogeneous shear turbulence

Joerg Schumacher
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Abstract

A statistically stationary and nearly homogeneous turbulent shear flow is established by an additional volume forcing in combination with stress-free boundary conditions in the shear direction. Both turbulent energy and enstrophy are stationary to a much better approximation than in previous simulations that use remeshing. The temporal fluctuations decrease with increasing Reynolds number. Energy spectra and shear-stress cospectra show that local isotropy is satisfactorily obeyed at the level of second-order moments. However, derivative moments of high-order up to n=7 yield increasing moments for n>=4 for the spanwise vorticity and the transverse derivative of the streamwise velocity in the range of Taylor Reynolds numbers 59<R_lambda<99. These findings, which are in apparent violation of local isotropy, agree with recent measurements.

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Joerg Schumacher. 2001-07-29. Derivative moments in stationary homogeneous shear turbulence. https://doi.org/10.1017/s0022112001005031

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