Behaviours of Energy Spectrum at Low Reynolds Numbers in Grid Turbulence
This paper reports an experimental investigation of the energy spectrum of turbulent velocity fields at low Reynolds numbers in grid turbulence. Hot wire measurements are carried out in grid turbulence with subjected to a 1.36:1 contraction of the wind tunnel. Three different grids are used: (i) large square perforated grid (mesh size 43.75mm), (ii) small square perforated grid (mesh size 14. and (iii) woven mesh grid (mesh size 5mm). The results indicate that the energy spectrum at small Reynolds numbers does not follow Kolmogorov’s universal scaling. It is further found that the critical Reynolds number, below which the scaling breaks down, is around 25.
Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1089297Procedia APA BibTeX Chicago EndNote Harvard JSON MLA RIS XML ISO 690 PDF Downloads 2043
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