Predicting wind turbine aerodynamic loads using laser scanned blade geometry with validation based on operational and structural data

Abstract. Aeroelastic wind turbine models are key tools in lifetime extension studies, but their application is often hindered by high uncertainty in aerodynamic load predictions. Manufacturers typically do not disclose blade geometry, which drives aerodynamic loading and is therefore an essential input. Furthermore, model outputs are often only compared with Supervisory Control and Data Acquisition (SCADA) data, which contains limited information on structural loading. The present work addresses these challenges by using experimental measurements to develop and validate an aeroelastic model of a utility-scale wind turbine. Results from the terrestrial laser scanning of a wind turbine blade are processed with a new methodology based on consensus algorithms to derive spanwise chord, twist, and airfoil distributions, which are used as OpenFAST inputs. Simulation results are compared with structural health monitoring measurements of tower bending moments at two elevations, in addition to SCADA data. Moreover, rotor thrust and torque are estimated from the tower measurements and used as additional comparison metrics. The simulations show good agreement with the experimental data, supporting the proposed methodology. A parametric study investigates how several uncertainties in the model inputs affect the predicted aerodynamic loads. The results highlight the usefulness of laser scanning for improving confidence in aerodynamic model inputs, as well as the value of tower load measurements as a complementary validation source to SCADA data. Therefore, the paper proposes and validates a new strategy to obtain a highly reliable model for load estimation, using a quite unique set of diverse measurements and new data processing approaches.