ID:
publications-1026
Type:
PEER_REVIEWED_ARTICLE
Year:
2015
Authors:
S. Laizet , J. NediΔ , J. C. Vassilicos
Title:
The spatial origin of β5/3 spectra in grid-generated turbulence
Venue/Journal:
DOI:
10.1063/1.4923042
Research type:
Simulation & Modeling
Water System:
River Basins
Technical Focus:
Abstract:
A combined wind tunnel and computational study of grid-generated turbulence along the centreline shows that the close to β5/3 power law signature of energy spectra in the frequency domain originates relatively close to the grid not only where the velocity derivative statistics become quite suddenly isotropic but also where the turbulent fluctuating velocities are very intermittent and non-Gaussian. As the inlet flow velocity increases, these power laws are increasingly well defined and increasingly close to β5/3 over an increasing range of frequencies. However, this range continuously decreases with streamwise distance from the grid even though the local Reynolds number first increases and then decreases along the same streamwise extent. The intermittency at the point of origin of the close to β5/3 power spectra consists of alternations between intense vortex tube clusters with shallow broad-band spectra and quiescent regions where the velocity fluctuations are smooth with steep energy spectra.
Link with Projects:
320560
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