Modelling the wind energy resources in complex terrain and atmospheres. Numerical simulation and wind tunnel investigation of non-neutral forest canopy flows

A series of experiments have been conducted in a stratifiable Atmospheric Boundary Layer (ABL) wind tunnel, using neutral and stable conditions, in which a forest canopy has been represented by use of architectural model trees. These experiments have been replicated in Computation Fluid Dynamic (CFD) simulations using a previously validated methodology. Both the numerical simulations and the experimental data show that atmospheric stability has a significant effect on the development and extent of the forest wake and on the prevalence of the canopy flow features such as the sub-canopy jet. The analysis shows that it is possible to include both forestry and buoyancy effects in numerical simulations using two sets of source and sink terms and achieve satisfactory convergence. However, it is shown that the numerical simulations overestimate the effects of thermal stratification when using the standard configuration.