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A mixed one-equation subgrid model for large-eddy simulation

Sinisa Krajnovic (Institutionen för termo- och fluiddynamik) ; Lars Davidson (Institutionen för termo- och fluiddynamik)
International Journal of Heat and Fluid Flow (0142-727X). Vol. 23 (2002), 4, p. 413-425.
[Artikel, refereegranskad vetenskaplig]

A new mixed one-equation subgrid-scale (SGS) model for large-eddy simulation is presented. The scale-similarity part of the model is used for the description of the local energy transport (Domaradzki et al., 1993, 1994), i.e. the energy transport between scales very close to the cut-off. The eddy-viscosity part of the model represents the non-local transfer of energy, i.e. the transfer between all scales smaller than grid-filter size Delta and larger than Delta. A priori tests done by Bardina et al. (1980) have shown a high correlation between the scale-similarity model and the exact SGS stress, tau(ij). The magnitude of the scale-similarity part in the mixed one-equation SGS model is either larger than or equal to that of the eddy-viscosity part. The modeled SGS stress is thus expected to correlate well with the exact stress, tau(jj). In the proposed model, the SGS kinetic energy, k(sgs), is used to obtain the velocity scale for the eddy-viscosity part of the model. The modeled k(sgs) equation is derived and contains some additional scale-similarity parts as compared with the k(sgs) equation used in the models of Ghosal et al. (1995) or Davidson (1997). It has been shown that the model is Galilean invariant and realizable. Moreover, the approximately correct near-wall behavior of the model has been proven. The model was tested for both channel flow and the case of a surface-mounted cube (Martinuzzi and Tropea, 1993). It was found that the model gives accurate results in both cases.

Nyckelord: Large-eddy simulation, Mixed dynamic subgrid-scale model, Subgrid-scale kinetic energy



Denna post skapades 2006-08-25. Senast ändrad 2017-10-03.
CPL Pubid: 10442

 

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Institutioner (Chalmers)

Institutionen för termo- och fluiddynamik (1989-2004)

Ämnesområden

Strömningsmekanik

Chalmers infrastruktur

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