Behaviours of Energy Spectrum at Low Reynolds Numbers in Grid Turbulence
نویسندگان
چکیده
Abstract—This paper reports an experimental investigation of the energy spectrum of turbulent velocity fields at low Reynolds numbers (Rλ) 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 43.75 mm), (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 Rλ does not follow Kolmogorov’s universal scaling. It is further found that the critical Reynolds number, Rλ,c below which the scaling breaks down, is around 25.
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