A turbulence model for 3-d flows with anisotropic structure of turbulence

• Autorzy: Czernuszenko W. , Rylov A.
• Języki publikacji: EN

Abstrakty

EN

A new turbulence model for flows in open channels with compound cross-sections is presented. The structure of turbulence in these channels can be anisotropic. This structure is described by the turbulent stress tensor that is presented here as the sum of two tensors, namely, normal and shear stress tensors. The normal and shear turbulent stresses are expressed by the turbulence intensities and the mixing length tensor (MLT), respectively. The turbulence intensities can be learned from measurements or another suitable approaches. One such approach that allows calculating the main component of the normal stresses is presented in the paper. The components of MLT are defined based on a new concept of generic mixing length (GML). The generic mixing length is assumed to depend on both distances; from the nearest wall and from the water surface. To demonstrate how the new model works the basic hydrodynamic equations (parabolic approximation of Reynolds equations) together with the turbulence model are solved. The well-known Patankar and Spalding (1972) algorithm was used when solving these equations. A series of numerical simulations were performed for different components of MLT and different channel geometries.

Słowa kluczowe

EN

3D flow; mathematical model; numerical simulation; open channel flow; turbulence model

• Wydawca: Institute of Hydro-Engineering of Polish Academy of Sciences
• Czasopismo: Archives of Hydro-Engineering and Environmental Mechanics
• Rocznik: 2005
• Tom: Vol. 52, nr 4
• Strony: 303--320
• Opis fizyczny: Bibliogr. 13 poz., il.

Twórcy

autor

Czernuszenko W.

• Polish Academy of Sciences, Institute of Geophysics, Ks. Janusza 64, 01-452 Warsaw, Poland

autor

Rylov A.

• Institute for Water and Environmental Problems, Papanintsev 105, Barnaul, Russia

Bibliografia

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