Variable Geometry Wind Turbine Blade Design

In addressing the challenges posed by wind turbine blades operating outside their normal speed ranges, our research focused on developing a morphing blade design that adapted lengthwise geometry to optimize power output. This innovation enhanced efficiency in small-scale wind turbines and contributed to the long-term sustainability of renewable energy.

To expand the operational range of wind turbines, we modified the chordwise properties of the airfoil profile on the turbine blade. This adaptability allowed for a more versatile performance across different wind speeds. Simulations and experiments focused on ensuring aerodynamic efficiency while balancing the trade-offs between power generation and structural stability.

Our approach aligned with established design standards, particularly IEC 61400, to ensure safety and compliance. We also referenced supplementary standards like IEC 60034 and ISO 4354 to prioritize quality and structural integrity.

Using the National Renewable Energy Laboratory’s OpenFAST simulation tool, we conducted aerodynamic analyses of the Enertech E44/40 wind turbine. Our simulations revealed that a 10% full-body length extension could increase power output by 49% at optimal wind speeds. Conversely, tip extensions produced more modest gains, emphasizing the balance between performance and design complexity.

Testing was conducted at the Cooper Union’s Aerolab Educational Wind Tunnel. Despite the wind tunnel’s limitations in achieving specified maximum speeds, our calibration established a relationship between input frequency and wind speed, crucial for accurate testing.

To overcome fabrication challenges, we utilized advanced 3D printing techniques. Our initial use of Ultimaker S5 printers transitioned to Formlabs Form 3 stereolithographic printers, allowing for high-resolution production of turbine blades, ensuring both strength and smooth surface quality.