Resonant enhancement of turbulent energy dissipation.
نویسندگان
چکیده
We periodically modulate a turbulent wind-tunnel flow with an active grid. We find a resonant enhancement of the mean turbulent dissipation rate at a modulation frequency which equals the large-eddy turnover rate. Thus, we find the best frequency to inject energy into a turbulent flow. The resonant response is characterized by the emergence of vortical structures in the flow and depends on the spatial mode of the stirring grid.
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ورودعنوان ژورنال:
- Physical review letters
دوره 105 4 شماره
صفحات -
تاریخ انتشار 2010