• Dr. James Brasseur
  • The Pennsylvania State University
  • 108 Surge Building
  • 4:00 p.m.
  • Faculty Host: Dr. Eric Paterson

The design and control of future generations of advanced commercial wind turbines will benefit from detailed quantifications of the interactions between the turbulence within the lower atmospheric boundary layer and the large variations in stresses on the blade surfaces in time and along blade span. In particular, the more energetic turbulent motions in the atmospheric surface layer, the region dominated by commercial wind turbines, are of order the rotor disk in scale and vary in structure depending on atmospheric stability and surface topography. As these energetic atmospheric eddies sweep through the rotor disk, they change the magnitude and the angle-of-attack of the incoming velocity vector relative to the rotating blades, leading to rapid changes in blade surface boundary layer structure, large variability in surface stresses and, consequently, large temporal fluctuations in blade and shaft bending moments, shaft torque and turbine power. Consequences include reduced reliability through premature blade, bearing and gearbox failure, and suboptimal control strategies. I shall describe a DOE-funded program to develop the Penn State "Cyber Wind Facility," a unique ‘experimental’ capability using petascale computer resources and the latest technologies in high-performance computing to collect ‘data’ for advanced wind turbine research, analysis and design. By integrating high-fidelity large-eddy simulation of the atmospheric boundary layer with high-resolution hybrid URANS-LES, and by including blade elasticity, tower deformation, and platform-wave interactions in offshore configurations, the Cyber Wind Facility is conceptualized akin to a full-scale wind turbine field facility designed to generate the highest fidelity most well-resolved 4-D data possible simultaneously over the entire wind turbine domain, for both onshore and offshore wind turbines. Planned extensions include turbine-turbine interactions and the improvement of actuator line methods for wind farm simulation.