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Remote wind sensing technologies, such as lidar, are becoming more and more mature and the wind energy industry is rapidly adopting them for a variety of purposes. One of these use cases is utilizing lidar measurements from a nacelle mounted device in order to improve the accuracy of load simulations by creating more realistic synthetic wind inputs. In this work we present an open source numerical framework, called ViConDAR for "Virtual Constrained turbulence and liDAR measurements", used for simulating lidar measurements and applying them as constraints in synthetic wind field generation. A realistic lidar simulator is used to obtain the virtual lidar measurements by scanning a synthetic wind field. These measurements are fed to open source constrained turbulence generation codes (TurbSim and PyConTurb), coupled to ViConDAR. The resulting constrained wind fields are compared to the original ones in order to quantify the level of convergence and can be used directly as inputs to aeroelastic simulations. Finally, two indicative applications of this framework are shown. First, a sensitivity analysis of the lidar parameters versus varying atmospheric conditions is carried out to investigate the potential of the lidar measurements to capture the wind field properties. Secondly, a sensitivity analysis is presented on the influence of different lidar parameters on the convergence of the full wind fields comparing both turbulence generation codes under varying atmospheric conditions.

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Reference wind turbines (RWTs) that reflect the state-of-the-art of current wind energy technology are necessary in order to properly evaluate innovative methods in wind turbine design and evaluation. The International Energy Agency (IEA) Wind Technology Collaboration Platform (TCP) Task 37 has recently developed a new RWT geared towards offshore floating-foundation applications: the IEA Wind 15 MW. The model has been implemented in two aeroelastic codes, OpenFAST and HAWC2, based on an underlying common ontology. However, these toolchains result in slightly different structural parameters, and the two codes utilise different structural models. Thus, to increase the utility of the model, it is necessary to compare the aeroelastic responses. This paper compares aeroelastic loads calculated using different fidelities of the blade model in OpenFAST (ElastoDyn and BeamDyn) and HAWC2 (prismatic Timoshenko without torsion and Timoshenko with fully populated stiffness matrix), where both codes use the DTU Basic controller and the same turbulence boxes to reduce discrepancies. The aeroelastic responses to steady wind, step wind and turbulent wind (per IEC 61400-1 wind class IB) are considered. The results indicate a generally good agreement between the loads dominated by aerodynamic thrust and force, especially for the no-torsion blade models. Discrepancies were observed in other load channels, partially due to differences in the asymmetric loading of the rotor and partially due to differing closed-loop dynamics, and they will be the subject of future investigations.