## Results Summary and Implications

This figure shows the relationship between the coefficient of power and the tip speed ratio for various wind turbines. This is used to analyze the effectiveness of our turbine and to predict how our model will perform when the model is scaled up.

To create our coefficient of power vs. tip speed ratio curve, more equations needed to be performed. The coefficient of power is the ratio of the actual power that the turbine produces to the ideal power that can be obtained by the wind turbine. The following equation was used:

Where ρ is the air density, A is the swept area of the blades, and vo is the speed of the wind. The tip speed ratio was calculated using the following equation:

Where ω is the angular velocity (in radians), calculated using the measured speed of the blades, r is the radius of the turbine, and vo is the speed of the wind. This figure shows our coefficient of power vs. tip speed ratio curve.

This figure shows where our results fall on the ideal coefficient of power vs. tip speed ratio curve.

Our results fall outside of the optimal portion of the curve for the Darrieus model, therefore we would not recommend that our particular design be manufactured and produced. A summary of our results can be seen in this table.

Adjusting the geometry of the blades and the radius of the model would increase the tip speed ratio and get the results closer to the optimal area of the graph. While our results were not optimal, we continued with the dimensional analysis so that when we came up with a design that met our specifications we could perform the same analysis. Keeping the coefficient of power for each wind speed constant, the swept area was adjusted to the new dimensions for our proposed full-scale product, which gave the projected power outputs. This can be seen in this figure.

Ideally we would use this data to pick the rest of the components for the model. Ideally we would use a small DC motor and appropriate gearing ratio to make the turbine spin at the appropriate speed such that the wind can take over. We would also need a solar panel and geared motor as part of the system for a commercialized product.