the wheel looks to be in pretty good order.... would it take much to get it running ? or do you have any idea of it's design speed ?
most wheels have the same perifial speed - mine is 5rpm on a 15' wheel - so 7rpm would be about right
that would be the easiest way to work out the flow ?
no - see robs comment
tho I guess if it was only used part of the year, then it would be designed for the flow at that time of year only ?
if you intend to charge batteries... it should be pretty easy to use a big 48v alternator as a generator
(they're a bit like car alternators but bigger made for powering things like those big American motor homes)
they have to spin like billio to get them to work. thats quite difficult to achieve.
giving you an advantage an you'll have a very wide rpm range to work with, something like 1000 to 8000 rpm
(once it's geared up from the wheel)
you never want an 8 times overspeed on a waterwheel - that would be Very Bad.
if you use one which can generate more power than your wheel could possible produce then it would also prevent any problems with overspeed etc...
then efficiency drops off very quickly. I tried that.
but you would need some decent dump loads, and a decent dump load system to take all the extra power if your batteries were full)
(like some electrical heaters etc..)
Find a wind turbine 'head' that does 48v - try miniwind for example (I had the high voltage versions) they spin quite slowly, so the gearing is simpler.
My gearing is just a big (5 foot) sprocket on the wheel shaft, a small (6") sprocket on a 2" diameter layshaft (that you can see bending when its running at full whack) - the layshaft then has a big (4') pulley driving a small pulley on the wind turbine head. Its going to be replaced with a similar thing to Noah's gearbox - its a huge 1/2 ton mining machine gearbox with a 4" slow shaft and a 2" fast shaft. I bought mine cheap from llewellins gears in Bristol. http://www.llewellins.co.uk
Power - my wheel is 15' diameter and 6' across. I have generated 7kw max - but have calculated that I could do about 15 in theory. 7 is a scary amount of water. Lets say you take the 15 as right - your wheel is 10/15ths the diameter, and 1/6th wide - 15 x .6666 x .16666 = 1.666kW
Thats about right for one of the miniwind generators or a 1.8kW ginlong at 500rpm ishhttp://www.ginlong.com/wind-turbine-pmg-pma-permanent-magnet-generator-alternator-GL-PMG-1800.htm