Bubbly turbulent drag reduction is a boundary layer effect.
نویسندگان
چکیده
In turbulent Taylor-Couette flow, the injection of bubbles reduces the overall drag. On the other hand, rough walls enhance the overall drag. In this work, we inject bubbles into turbulent Taylor-Couette flow with rough walls (with a Reynolds number up to 4 x 10(5), finding an enhancement of the dimensionless drag as compared to the case without bubbles. The dimensional drag is unchanged. As in the rough-wall case no smooth boundary layers can develop, the results demonstrate that bubbly drag reduction is a pure boundary layer effect.
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ورودعنوان ژورنال:
- Physical review letters
دوره 98 8 شماره
صفحات -
تاریخ انتشار 2007