Turbulence and Shear Flow Phenomena -1 First International Symposium

ISBN Print: 1-56700-135-1

Statistical turbulence models to simulate turbulence emergence in atmosphere.

Аннотация

The paper examines the computational modelling of the stably stratified atmosphere in the case of gravity wave breaking which induces turbulence generation and its transport in the whole atmosphere. The two first-order models developed for stably stratified flows by Abart and Sini, 1997 and validated on the LES of Kaltenbach et al., 1994 (stably stratified and shear flow) are applied to the simulation of the Boulder storm, 1972. In the atmosphere, the Reynolds number may be very high. An extansion of the standard e equation to these high Reynolds number allows to simulate the unsteady behaviour of the storm. The first-order models adapted to the stably stratified flows achieves well in the simulation of the generation, transport and diffusion of the turbulent kinetic energy k in the atmosphere contrary to the standard k-ε model and the k-L model where L is an integral length scale used to prescribe the dissipation rate ε.