Validation of a CFD model with a synchronized triple-lidar system in the wind turbine induction zone

Monday 20 Mar 17


Alexander Meyer Forsting
DTU Wind Energy
+45 93 51 11 75

CFD model of a wind turbine inflow (induction zone) was validated by comparison to 3D measurements within this zone using the triple lidar system (DTU short range WindScanner). In this paper, Alexander R. Meyer Forsting et al. present a novel probabilistic validation procedure and the related uncertainty:

Paper abstract:

A novel validation methodology allows verifying a CFD model over the entire wind turbine induction zone using measurements from three synchronized lidars. The validation procedure relies on spatially discretizing the probability density function of the measured free-stream wind speed. The resulting distributions are reproduced numerically by weighting steady-state Reynolds averaged Navier-Stokes simulations accordingly. The only input varying between these computations is the velocity at the inlet boundary. The rotor is modelled using an actuator disc. So as to compare lidar and simulations, the spatial and temporal uncertainty of the measurements is quantified and propagated through the data processing. For all velocity components the maximal difference between measurements and model are below 4.5% relative to the average wind speed for most of the validation space. This applies to both mean and standard deviation. One rotor radius upstream the difference reaches maximally 1.3% for the axial component.
13 DECEMBER 2018