Naslov
A total turbulent energy closure model for neutrally and stably stratified atmospheric boundary layers

Autori
Mauritsen, Thorsten ; Svensson, Gunilla ; Zilitinkevich, Sergej ; Esau, Igor ; Enger, Leif ; Grisogono, Branko

Izvornik
Journal of the Atmospheric Sciences (0022-4928) 64 (2007), 11; 4113-4126

Vrsta, podvrsta i kategorija rada
Radovi u časopisima, članak, znanstveni

Ključne riječi
turbulence; closure; parameterization; Richardson number; Prandtl number

Sažetak
We present a turbulence closure for neutral and stratified atmospheric conditions. The closure is based on the concept of the total turbulent energy. The total turbulent energy is the sum of the turbulent kinetic energy and turbulent potential energy, which is proportional to the potential temperature variance. The closure uses recent observational findings to take into account the mean-flow stability. These observations indicate that turbulent transfer of heat and momentum behaves differently under very stable stratification. Whereas the turbulent heat-flux tends to zero beyond a certain stability limit, the turbulent stress stays finite. The suggested scheme avoids the problem of self-correlation. The latter is an improvement over the widely used Monin-Obukhov based closures. Numerous large-eddy simulations, including a wide range of neutral and stably stratified cases, are used to estimate likely values of two free constants. In a benchmark case the new turbulence closure performs indistinguishably from independent large-eddy simulations.

Izvorni jezik
Engleski

Znanstvena područja
Geologija

POVEZANOST RADA