ar X iv : p hy si cs / 0 61 11 95 v 1 2 1 N ov 2 00 6 The phase - locked mean impulse response of a turbulent channel flow
نویسنده
چکیده
We describe the first DNS-based measurement of the complete mean response of a turbulent channel flow to small external disturbances. Space-time impulsive perturbations are applied at one channel wall, and the linear response describes their mean effect on the flow field as a function of spatial and temporal separations. The turbulent response is shown to differ from the response a laminar flow with the turbulent mean velocity profile as base flow.
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