One of my design projects at the University of Pennsylvania involved designing and bulding a vertical axis wind turbine to generate electical power. We worked in a team of 3 and the goal was to maximise electrical power generation. The design process involved several steps including: predicting turbine performance by testing a small-scale model, designing a transmission between the turbine and DC motor used as a generator and selecting appropriate electrical load (resistor) to which the power was delivered.

First of all, we had to decide whether we will build a drag-based Savonius or a lift-based Darrieus wind turbine. The differences in the design between the two made the Darrieus wind turbine more difficult to manufacture but also capable of generating more power. Because of an extra challenge and as maximising power generation was the goal of the task, we decided to build thex lift-based turbine.

Before full-scale construction, a series of wind tunnel tests were performed. We tested 4 different Darriues and 2 Savonius turbine designs which were made out of cardboard, lasercut parts or 3D printed parts. We then nondimensionalised the data to make predictions of the aerodynamic characteristics and energy generation of the full-scale device.
The most effective design was picked for full-scale manufacturing. The turbine was built from a variety of different parts which included: laser-cut balsa and MDF wing profiles, aluminium bars and cardboard tubes, 3D printed connections and MonoKote coating of the airfoils.
The most effective design was picked for full-scale manufacturing. The turbine was built from a variety of different parts which included: laser-cut balsa and MDF wing profiles, aluminium bars and cardboard tubes, 3D printed connections and MonoKote coating of the airfoils.
CAD model of the final lift-based (Darrieus) wind turbine.
CAD model of the final lift-based (Darrieus) wind turbine.
Successful wind turbine outdoor test.