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How do different gases behave when subjected to turbulence in a wind tunnel?

Reynolds decomposition

K-epsilon turbulence model

Reynolds number

K-omega turbulence model

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Different gases exhibit varying behaviors when exposed to turbulence in a wind tunnel. For instance, the dispersion of gases like carbon dioxide and sulfur hexafluoride under different Reynolds number regimes can lead to concentration fluctuations and time series variations, impacting ventilation system design and operation. In another study, large-scale turbulent motions in the wind tunnel were found to enhance horizontal gas spread, affecting the balance of processes involved and altering gas concentration distributions. Additionally, the analysis of energy dissipation rates in grid turbulence revealed the presence of coherent and incoherent elements influencing the probability density functions, showcasing the complex nature of gas dynamics in turbulent environments. These findings highlight the diverse responses of gases to turbulence, emphasizing the need for comprehensive understanding in various scenarios.

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Open access•Journal Article•DOI Analyses of turbulence in a wind tunnel by a multifractal theory for probability density functions Toshihico Arimitsu, Naoko Arimitsu, Hideaki Mouri - Show less +2 more 17 Nov 2011-arXiv: Fluid Dynamics 3 Citations	Different gases subjected to turbulence in a wind tunnel exhibit varying behaviors, analyzed through multifractal theory for probability density functions, distinguishing between coherent and incoherent elements in fully developed turbulence.
Open access•Journal Article•DOI Variable density turbulence tunnel facility Eberhard Bodenschatz, Gregory P. Bewley, Holger Nobach, Michael Sinhuber, Haitao Xu - Show less +4 more 30 Sep 2014-Review of Scientific Instruments 56 Citations	Different gases like air, nitrogen, and sulfur hexafluoride (SF6) exhibit variable density turbulence behaviors in wind tunnels, allowing for adjustable kinematic viscosities and Reynolds numbers based on pressure levels.
Journal Article•DOI Wind-Tunnel Experiments for Gas Dispersion in an Atmospheric Boundary Layer with Large-Scale Turbulent Motion Takenobu Michioka, Ayumu Sato, Koichi Sada - Show less +2 more 19 Jul 2011-Boundary-Layer Meteorology 14 Citations	Different gases behave similarly when subjected to turbulence in a wind tunnel, with large-scale turbulent motions enhancing horizontal spread but having minimal effect on vertical gas dispersion.
Open access•Journal Article•DOI Experimental investigation on concentration profiles and fluctuations of dense gases in wind tunnel Mauro Gaggero, Andrea P. Reverberi, Bruno Fabiano - Show less +2 more 20 Aug 2015-Chemical engineering transactions	Different gases, such as carbon dioxide and sulphur hexafluoride, exhibit varying concentration profiles and fluctuations in a wind tunnel under different Reynolds number regimes, aiding in ventilation system optimization.

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