Isotropic-turbulence-induced mass transfer across a severely contaminated water surface. (24th May 2016)

• Record Type: Journal Article
• Authors: Herlina, H.; Wissink, J. G.
• Is Part Of: Journal of fluid mechanics. Volume 797(2016:Jun.)
• Page Start: 665
• Page End: 682
• Publication Date: 2016-05-24
• Subjects: air/sea interactions, -- computational methods, -- turbulent mixing; Fluid mechanics -- Periodicals; 532.005
• DOI: 10.1017/jfm.2016.278
• Languages: English
• ISSNs: 0022-1120

Abstract

Abstract : Direct numerical simulations were performed to investigate the effect of severe contamination on interfacial gas transfer in the presence of isotropic turbulence diffusing from below. A no-slip boundary condition was employed at the interface to model the severe contamination effect. The influence of both Schmidt number ( $Sc$ ) and turbulent Reynolds number ( $R_{T}$ ) on the transfer velocity ( $K_{L}$ ) was studied. In the range from $Sc=2$ up to $Sc=500$ it was found that $K_{L}\propto Sc^{-2/3}$, which is in agreement with predictions based on solid–liquid transport models, see e.g. Davies (1972, Turbulence Phenomena, Academic). For similar $R_{T}$, the transfer velocity was observed to reduce significantly compared with the free-slip conditions. The reduction becomes more pronounced with increasing Schmidt number. Similar to the observation for free-slip conditions made by Theofanous et al. ( Intl J. Heat Mass Transfer, vol. 19 (6), 1976, pp. 613–624), the normalized $K_{L}$ in the present no-slip case was also found to depend on $R_{T}^{-1/2}$ and $R_{T}^{-1/4}$ for small and large turbulent Reynolds numbers, respectively.