Dual-action Turbine

Turbine utilising a combination of direct impact and cross-flow propulsion.

This is based on the Ugrinsky turbine design with a simpler geometric construction composed of only circles.

These models spin well from breath power, but would probably need to be scaled up for use to generate useful amounts of electricity.

The most recent update of the model includes the following features:

* 3 pass-through channels, and 3 collecting blades
* spherical path extrusion to provide a greater attack surface