Validation and comparison of a newly developed aeroelastic design code for VAWT

The open source simulation code QBLADE, based on a Lifting Line Free Vortex Wake formulation to evaluate the unsteady aerodynamics, recently integrated the PROJECT-CHRONO FEA library that, by using Euler-Bernoulli beams in a corotational formulation, solves for the structural dynamics to achieve an aeroelastic coupling. To validate the newly implemented structural model its performance is compared to literature data and two other structural computer codes. The comparison is based on a modal analysis, steady- and aeroelastic simulations of the SNL 34m VAWT testbed for which the aerodynamic and structural properties are well known. The structural loads are obtained from IEC 61400-1 design load cases. In one of the calculated load cases an aeroelastic instability could be observed which confirms similar observations that have previously been reported in the literature.