Interaction between inner and outer layer in drag-reduced turbulent flows
نویسندگان
چکیده
منابع مشابه
The interaction between inner and outer regions of turbulent wall-bounded flow.
The nature of the interaction between the inner and outer regions of turbulent wall-bounded flow is examined. Townsend's theory of inactive motion is shown to be a first-order, linear approximation of the effect of the large eddies at the surface that acts as a quasi-inviscid, low-frequency modulation of the shear-stress-bearing motion. This is shown to be a 'strong' asymptotic condition that d...
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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...
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ژورنال
عنوان ژورنال: PAMM
سال: 2016
ISSN: 1617-7061
DOI: 10.1002/pamm.201610305