Francis Turbine Runner

The Francis turbine is arguably the most efficient type of hydropower turbine taking advantage of both reaction and impulse characteristics in order to get the most rotational energy out of the flowing water. The unique part of the design is how the blade curves over at the outlet (the top in this image) where water has to push against this, increasing rotational motion. The geometry of the runner is reasonably complex but after a while, I found that using the boundary boss extrude made it simple to produce the blade profile. 

This runner is just one part of the Francis turbine which also requires a volute and stator blades. I made this runner as practice to learn how to model it since a Francis turbine may be used in my A level project.

Below: A glass render so that the blade profile is more easily visible.