Should be fairly easy to build a load cell : start with a 55 gal drum,
the kind where one of the heads seals on with a band clamp. Get a
length of shaft (1" dia would probably work, 1.5" would allow some
margin) and weld some 'paddles' to it to stir the drum. Mount the shaft
through the center of the barrel, with some pillow block bearings, then
turn the whole mess on it's side (shaft horizontal) and use some more
pillow blocks to mount the shaft to stands, so that the drum is free to
turn on the shaft, and the shaft is also free to turn. Add a lever arm
(of known length) to the drum, and water fittings at the top and
bottom. (Probably also need an air vent at the top, with baffles.)
Hook a garden hose through a ball valve to the upper fitting, and a
drain with some restriction (maybe another ball valve) to the bottom.
Some kind of scale on the lever arm (eg a calibrated spring), and a
tachometer on the shaft, gives you the info to calculate horsepower, and
the water valve gives you the load control (more water = more load). A
little work with a calculator (ie how many gpm of water does it take to
carry away the amount of heat you plan to generate) should give you an
idea of the restriction to place in the drain line.
Hooking this contraption to an engine might be a little tougher <g>
Please note : this is strictly a 'blue sky' design on my part. If you
build it, and it blows up, I'm not responsible. However, if you do
build it, I'd like to hear about your results.
Randall
> Uncle Jacks wondered:
>
> > Has anyone on the list either built their own engine dynamometer or have
> > any information on doing it?
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