Vertical Axis Wind Turbine
We designed and tested Lenz and Savonius 7 x 7 inch scale models in a wind tunnel and used Reynolds number scaling with dimensionless Cp vs. TSR data to optimize for our full scale 1 x 0.75 meter turbine, coming first in class with 6.64 Watts of power produced with the lowest weight of 2.33 kg.
Our testing procedure consisted of choosing a constant wind speed and varying resistances while measuring the RPM of the turbine and the voltage across the resistor. We tested a 3 blade Lenz as well as both 3 and 2 blade Savonius designs. Using this data we found the coefficient of power and the tip speed ratio. Since Cp and TSR are dimensionless, we can predict the performance of each turbine at full scale. After several trials we compiled the results for Cp vs TSR into the graph below which shows that the 2 blade Savonius was the best performing design with consistent and complete data.
Design Iterations:
Data from actual run. Readings before ~38s are test spins by hand.
Team Members: Josh Ren, Mohamed Elshabrawishy