The key design considerations were that the product needed to be cheap, easy to fabricate & easy to transport. This ruled out the possibility of building a single, large turbine.
The finally settled on this design.
In the center you can see a hole. The piece is slid onto a pole & then all pieces locked into place using the male - female connection points visible on the top & bottom.
When these individual pieces are stacked, they form the following shape.
This is 1.26 meters wide. Each DNA piece is 210mm high. Stack 20 together & the turbine is over 4 meters high.
To build a scale model, we 3D printed the parts.
We then mounted the model pieces on a model pole to check everything worked well..
As you can see, our little model even has ball bearings so we could test if it was spinning correctly. You can also see that our 3D printing efforts were not exactly perfect but good enough for proof of concept.
The next step was to make the FRP tooling & spend lots of time looking at how to mount the turbine, pole strength, finding suitable bearings etc. To be described in future project logs..
The idea of a DNA shaped turbine is not new. Various companies in China make them but not in a modular way. Also, one USA company spend about USD70M of investors money developing a ''Helix turbine". After running out of money, they were bought by another company but I believe the product they developed it no longer available. Unfortunately, in the land of green products, a lot of companies seen to waste millions hyping products that could never repay the massive development costs. After burning through the investors money, a lot of these companies just go bankrupt & the product is never heard of again..