A numerical framework for constraining synthetic wind fields with lidar measurements for improved load simulations

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.