It would depend on your specific wheel. There's a number of design features that go into the wheel which will influence the motion. I thought about modeling the wheel and in so doing, I realized there were a host of factors that would need to be taken into account, such as:

1. Rotational inertia of wheel

2. Friction of wheel

3. Size of buckets

4. Size of hole in bottom of bucket

5. Spacing of water buckets (ie: is there always a bucket under the water or are there gaps?)

6. Angle wheel makes with vertical (I read some experimenters tried to limit rotational forces by tilting the wheel)

7. Where around the circle the buckets are being filled

etc...

One web page suggested that their attempts to model this wheel required tilting the wheel over to minimize rotational torque from the water and minimizing flow. They also had problems with friction of the wheel.

http://www.ace.gatech.edu/experiments2/ ... nz/fall02/