Mechanical Engineering Commons^™

Integrated Design Of Downwind Land-Based Wind Turbines Using Analytic Gradients, Andrew Ning, Derek Petch

Faculty Publications

Wind turbines are complex systems where component-level changes can have significant system-level effects. Effective wind turbine optimization generally requires an integrated analysis approach with a large number of design variables. Optimizing across large variable sets is orders of magnitude more efficient with gradient-based methods as compared to gradient-free method, particularly when using exact gradients. We have developed a wind turbine analysis set of over 100 components where 90% of the models provide numerically exact gradients through symbolic differentiation, automatic differentiation, and adjoint methods. This framework is applied to a specific design study focused on downwind land-based wind turbines.

Downwind machines …

Comparison Of Airfoil Precomputational Analysis Methods For Optimization Of Wind Turbine Blades, Ryan Barrett, Andrew Ning

Faculty Publications

The objective of this research was to develop and compare various airfoil precomputational parameterization and analysis techniques for aerostructural optimization of wind turbine blades. The airfoils along the blade were added as optimization design variables through pre-computational parameterization methods using thickness-to-chord ratios and blended airfoil family factors. The airfoils' aerodynamic performance was analyzed with three methods of increasing fidelity: a panel method (XFOIL), Navier-Stokes based computational fluid dynamics (RANS CFD), and wind tunnel data. The optimizations minimized mass over annual energy production (m/AEP) and thereby approximated the minimization of cost of energy. The results were compared to the NREL 5-MW …