Large-Eddy Simulation Study of Thermally Stratified Canopy Flow
Artikel i vetenskaplig tidskrift, 2015

A number of large-eddy simulations (LES) are performed for the calculation of the airflow over a horizontally homogeneous forest canopy for a wide range of thermal stability classes. For the first time, results from LES of a stably stratified canopy are also presented. Simulation results compare favourably to recent field measurements over a pine forest in south-eastern Sweden. The simple heat source model was found to perform adequately and to yield within-canopy heat-flux profiles typically observed for stable conditions in the field. Evidence was found for a layer of unstably stratified air in the canopy trunk space under stable stratification. The importance of a secondary wind-speed maximum is emphasized in stable conditions. Examination of the budget equation of turbulent kinetic energy (TKE) revealed that, during stable stratification, pressure transport plays an increasingly important role in supplying the canopy region with TKE.

Forest turbulence

Large-eddy simulation

Atmospheric boundary layer

Thermal stratification

Forest canopy

Turbulent kinetic energy budget

Författare

Bastian Nebenführ

Svensk Vindkraftstekniskt Centrum (SWPTC)

Chalmers, Tillämpad mekanik, Strömningslära

Lars Davidson

Chalmers, Tillämpad mekanik, Strömningslära

Svensk Vindkraftstekniskt Centrum (SWPTC)

Boundary-Layer Meteorology

0006-8314 (ISSN) 1573-1472 (eISSN)

Vol. 156 2 253-276

Drivkrafter

Hållbar utveckling

Ämneskategorier

Fysik

Strömningsmekanik och akustik

DOI

10.1007/s10546-015-0025-9