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arXiv · 2412.10645

Turbulent/non-turbulent interface in high Reynolds number pressure gradient boundary layers

Ivan Marusic·Wagih Abu Rowin·Mitchell Lozier·Luka Lindić·Ahmad Zarei·Rahul Deshpande
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Abstract

We report two-dimensional particle image velocimetry experiments in high Reynolds number turbulent boundary layers imposed with a moderately strong streamwise pressure gradient. The unique aspect of these data are the highly resolved measurements across the outer region of a physically thick boundary layer, enabling accurate detection of turbulent/non-turbulent interfaces (TNTI). The present dataset is used to detect the TNTI of an adverse pressure gradient turbulent boundary layer and compare its characteristics with that for a zero-pressure gradient boundary layer, at a nominally similar friction Reynolds number. It is found that the TNTI exists across a broader range of wall-normal distance in presence of an adverse pressure gradient, as compared to the zero-pressure gradient case. Implications on conditionally averaged turbulence statistics are discussed based on detection of the TNTI.

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Ivan Marusic, Wagih Abu Rowin, Mitchell Lozier, Luka Lindić, Ahmad Zarei, Rahul Deshpande. 2024-12-14. Turbulent/non-turbulent interface in high Reynolds number pressure gradient boundary layers. https://arxiv.org/abs/2412.10645

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