Basal Pressure Variations Induced by a Turbulent Flow Over a Wavy Surface

Frontiers in Physics

Michel Louge¹  Philippe Claudin²  Bruno Andreotti² 

[1] Ithaca, NY, United States;Paris, France;

关键词: pressure modulation;    bedforms;    sinusoidal topography;    linear response;    laminar-turbulent transition;   

DOI  :  10.3389/fphy.2021.682564

来源: Frontiers

【 摘 要 】

Turbulent flows over wavy surfaces give rise to the formation of ripples, dunes and other natural bedforms. To predict how much sediment these flows transport, research has focused mainly on basal shear stress, which peaks upstream of the highest topography, and has largely ignored the corresponding pressure variations. In this article, we reanalyze old literature data, as well as more recent wind tunnel results, to shed a new light on pressure induced by a turbulent flow on a sinusoidal surface. While the Bernoulli effect increases the velocity above crests and reduces it in troughs, pressure exhibits variations that lag behind the topography. We extract the in-phase and in-quadrature components from streamwise pressure profiles and compare them to hydrodynamic predictions calibrated on shear stress data.

【 授权许可】

CC BY