D. Mironov TURBULENCE STRUCTURE AND MIXING IN STABLE . FLOWS OVER HETEROGENEOUS SURFACES

14 апреля 2021 г. 40-е заседание семинара: D. Mironov (1), P. Sullivan (2) (1) German Weather Service, Offenbach am Main, Germany (2) National Center for Atmospheric Research, Boulder, CO, USA TURBULENCE STRUCTURE AND MIXING INTENSITY IN STABLY STRATIFIED BOUNDARY-LAYER FLOWS OVER THERMALLY HETEROGENEOUS SURFACES The effect of horizontal thermal heterogeneity of the underlying surface on the turbulence structure and mixing intensity in stably stratified boundary-layer (SBL) flows is analysed. Weakly to moderately stable SBLs are examined using large-eddy simulation (LES), while direct numerical simulation (DNS) is used to tackle strongly stable SBLs. Idealized LES of SBL flows driven by fixed winds and homogeneous and heterogeneous surface temperature are compared. A canonical GABLS1 SBL is taken as a reference. The LES data are used to explore the flow structure, to compute statistical moments of the fluctuating fields, to estimate terms in the second-moment budgets, and to assess the relative importance