LES

Large eddy simulation

FAST-CENER

Submitted by Jose Azcona Arm... on June 24, 2015 - 12:37pm
Main hypothesis
CENER has expanded the FAST code by including their own modules as OPASS, for the simulation of mooring line dynamics, DYSTool, for the unsteady aerodynamics modeling or HydroVisc for the inclusion of viscous effects on submerged elements.

VestasFOAM 1.1.0 - LES/DES

Submitted by Yavor Hristov on May 5, 2015 - 12:00am
Main hypothesis

VestasFOAM 1.1.0 - DES is built upon the pimpleFoam solver packaged within the publically available OpenFOAM distribution [1]. The k-omega SST DES [2] turbulence model has been implemented in-house. If desired buoyancy can be selected through the Boussinesq approximation.

VestasFOAM - DES is used operationally to determine probability density functions of wind veer and wind shear and compliance with IEC standards for class A,B and C sites. This has been done with good success both forensically (i.e. once problems have been detected on old sites) and during the initial micro-siting activities when transient flow suspicions are raised on prospective sites.

VestasFOAM 1.1.0 - LES is built upon the SOWFA project led by NREL [3]. The SOWFA code has been modularized to fit within the VestasFOAM automated CFD workflows and linked to Vestas turbine libraries for efficient/automated case setup, execution and post-processing. Currently this is only valid on flat terrain/offshore.

For both LES/DES, grids are automatically generated in Pointwise [4] using a structured hyperbolic extrusion. Great care is taken to control grid quality, with small expansion ratios from terrain to rotor bottom, and uniform grid spacing through the turbine/wake areas. As with our steady process, when sufficiently vertically distanced from turbines, the horizontal mesh resolution is continually reduced in order to lower mesh size.

SOWFA - LES

Submitted by Matthew Churchfield on May 4, 2015 - 6:36pm
Main hypothesis

The large-eddy simulation (LES) solver within the Simulator for On/Offshore Wind Energy (SOWFA) is built upon the Open-source Field Operations And Manipulations (OpenFOAM) computational fluid dynamics (CFD) toolbox.  The solver is incompressible and uses the unstructured finite-volume formulation.  Buoyancy effects are included through a Boussinesq buoyancy forcing term.  Turbines are modeled with actuator lines.