GE Global Research and Sandia National Laboratories have research that could significantly impact the design of future wind turbine blades.
Using high-performance computing to perform complex calculations, engineers have overcome previous design constraints, allowing them to begin exploring ways to design re-engineered wind blades that are low-noise and are more prolific power-producers.
According to GE, its scope of work focused on advancing wind turbine blade noise prediction methods. Aerodynamic blade noise is the dominant noise source on modern, utility-scale wind turbines and represents a key constraint in wind turbine design. Efforts to reduce blade noise can help reduce the cost of wind energy and increase power output.
GE predicts that a 1-decibel quieter rotor design would result in a 2% increase in annual energy yield per turbine. With approximately 240 GW of new wind installations forecast globally over the next five years, a 2% increase would create more than 5 GW of additional wind power capacity.
‘There's no question; aerodynamic noise is a key constraint in wind turbine blade design today,’ explains Mark Jonkhof, wind technology platform leader at GE Global Research. ‘By using high-performance computing to advance current engineering models that are used to predict blade noise, we can build quieter rotors with greater blade tip velocity that produce more power. This not only means lower energy costs for consumers, but also a significant reduction in greenhouse gas emissions.’
To ensure that GE's wind blades do not pose noise issues, airfoil level acoustic measurements are performed in wind tunnels, field measurements are done to validate acceptable noise levels and noise-reducing operating modes are implemented in the control system. Better modeling will help maintain the current low noise levels while boosting output.
GE's testing involved Sandia's Red Mesa supercomputer's running a high-fidelity Large Eddy Simulation (LES) code, developed at Stanford University, to predict the detailed fluid dynamic phenomena and resulting wind blade noise.
For a period of three months, this LES simulation of the turbulent air flow past a wind blade section was continuously performed on the Red Mesa HPC. The resulting flow-field predictions yielded valuable insights that were used to assess current engineering design models, the assumptions they make that most impact noise predictions, and the accuracy and reliability of model choices.
‘We found that high fidelity models can play a key role in accurately predicting trailing edge noise,’ adds Jonkhof. "We believe that the results achieved from our simulations would, at the very least, lay the groundwork for improved noise design models.’