Actuator disk

ISOL RANS 0.1

Submitted by Carlos Peralta on May 4, 2015 - 6:02pm
Main hypothesis

Steady state solver based on OpenFOAM's simpleFoam (version 2.1.1). Isotropic eddy-viscosity turbulence using the Boussinesq approximation, homogeneous forest canopy and actuator disk solver.

DWM

Submitted by Gunner Chr. Larsen on May 4, 2015 - 5:39pm
Main hypothesis

The basic philosophy is to consider wakes as passive tracers continuously emitted from the wind farm turbines. The basic idea is a split of scales in the wake flow field, based on the conjecture that large turbulent eddies are responsible for stochastic wake meandering only, whereas small turbulent eddies are responsible for wake deficit attenuation and expansion in the meandering frame of reference as caused by turbulent mixing.

CRES-flow NS

John Prospathopoulos's picture
Submitted by John Prospathopoulos on May 4, 2015 - 5:22pm
Main hypothesis

CRES-flow NS is an in-house RANS solver using the k-ω turbulence model for closure and the actuator disk theory for the simulation of the embedded wind turbines. The momentum equations are numerically integrated introducing a matrix-free pressure correction algorithm which maintains the compatibility of the velocity and pressure field corrections. Discretization is performed with a finite volume technique using a body-fitted coordinate transformation on a structured curvilinear mesh. Convection terns are handled by a second order upwind scheme bounded through a limiter, whereas centred second order schemes are employed for the diffusion terms. Velocity-pressure decoupling is prevented by a linear fourth order dissipation term added into the continuity equation. The k-ω turbulence model has been suitably modified for atmospheric conditions. Stratification is considered through an additional production term added to each one of the k and ω transport equations to account for the buoyancy effect.