Wakes behind surface-mounted obstacles: Impact of aspect ratio, incident angle, and surface roughness

Research output: Contribution to journalArticle

Abstract

The so-called wake-moment coefficient Ch and lateral wake deflection of three-dimensional windbreaks are explored in the near and far wake. Wind-tunnel experiments were performed to study the functional dependence of Ch with windbreak aspect ratio, incidence angle, and the ratio of the windbreak height and surface roughness (h/z0). Supported with the data, we also propose basic models for the wake deflection of the windbreak in the near and far fields. The near-wake model is based on momentum conservation considering the drag on the windbreak, whereas the far-wake counterpart is based on existing models for wakes behind surface-mounted obstacles. Results show that Ch does not change with windbreak aspect ratios of 10 or greater; however, it may be lower for an aspect ratio of 5. Ch is found to change roughly with the cosine of the incidence angle, and to depend strongly on h/z0. The data broadly support the proposed wake-deflection models, though better predictions could be made with improved knowledge of the windbreak drag coefficient.

Original languageEnglish (US)
Article number033801
JournalPhysical Review Fluids
Volume3
Issue number3
DOIs
StatePublished - Mar 2018

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Wake
Surface Roughness
Aspect Ratio
Aspect ratio
Surface roughness
Angle
Deflection
Incidence
Drag Coefficient
Wind Tunnel
Near-field
Far Field
Drag
Drag coefficient
Model
Conservation
Lateral
Wind tunnels
Momentum
Moment

ASJC Scopus subject areas

  • Computational Mechanics
  • Modeling and Simulation
  • Fluid Flow and Transfer Processes

Cite this

Wakes behind surface-mounted obstacles : Impact of aspect ratio, incident angle, and surface roughness. / Tobin, Nicolas; Chamorro Chavez, Leonardo Patricio.

In: Physical Review Fluids, Vol. 3, No. 3, 033801, 03.2018.

Research output: Contribution to journalArticle

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