Effects of Wall Topology on Statistics of Cube-Roughened Wall Turbulence

نویسندگان

چکیده

In this work, we carried out roughness-resolved direct numerical simulations of cube-roughened turbulent channel flows to investigate the effects aligned and staggered arrangements, element spacings, orientations on statistics rough-wall turbulence. The results show that equivalent sandgrain roughness, Reynolds stresses dispersive are affected by spacings arrangements in different ways depending cube orientations. Placing roughness elements a way general increases unless when element–element interaction is insignificant for orientation with wakes short length. As normal streamwise component (both normalized total friction velocity), placing decreases their maximal values compared arrangements. spacing maximums stresses, similar trends observed increasing l/r (where r height) from 2.0 2.8. When further 2.8 3.5, however, greater components larger all considered surfaces. For turbulence wake element, certain similarities spacings.

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ژورنال

عنوان ژورنال: Boundary-Layer Meteorology

سال: 2022

ISSN: ['0006-8314', '1573-1472']

DOI: https://doi.org/10.1007/s10546-022-00760-3