How to Calculate Bucket Gap Width and Gap Width Ratio for a Savonius Turbine?

[MechaMZ]

Hi,

I'm going to design a savonius turbine, and image below is my turbine blade with dimension.

But I not sure how to determine the "bucket gap width, S" and "gap width ratio, s/d"
is there any calculation method for them??


thanks

 

[MechaMZ]

http://img258.imageshack.us/img258/6376/srotoryi7.jpg

there is a support beam in the centre of the turbine blades, and the diameter is 2cm. the bucket gap width is 6cm, the diameter of turbine is 44cm, and the height of the turbine blade is 80cm.

when calculating the "gap width ratio, s/d", do I need to take the diameter of the support beam into consideration?

so my gap width ratio = (bucket gap width,s - diameter of support beam) / diameter of turbine ??

or just ignore the diameter of the support beam?

thanks

 

[Enthalpy]

Avoiding any beam would be much better! Can't you weld the buckets on two sheets at the top and bottom and then mount a larger bearing?