Power/Weight ratio of a horse

is it still funny? after all this time?

Heh. If you like, although I was more meaning that even without doing any useful work, a horse will need to exert energy just to move about ("loss"). IF the horse is doing an amount of useful work ("work") the mechanical efficiency of the horse is (work)/(work + loss). To avoid tiring the horse, (work) can not be much larger than (loss), and so the efficiency is significantly less than 1. Also, the hose moves in lunges, compared to a steam engine, and so the non- linearities in the drivetrain (ropes pulleys etc..) losses will result in a further reduction of efficiency.

The steam engine delivers power in lumps too - max output is at about mid stroke when the piston is going fast and the crank to connecting rod angle is close to 90 deg giving max leverage. It uses a big flywheel to store the energy when it's putting more out than can be used by the load and releases that energy when the load is drawing more energy than the engine is delivering. No reason at all why the capstan on a horse driven mill can't or didn't do the same. The horse was always at the best working radius and could produce circular motion directly, it didn't have dead motion at the end of each stroke. Even with two legs you manage to walk at a steady pace. It was normal to put 4 to 8 horses on a capstan wheel so the power delivered would be very steady compared to the thrusts of a steam engine.

-- Peter Hill Spamtrap reply domain as per NNTP-Posting-Host in header Can of worms - what every fisherman wants. Can of worms - what every PC owner gets!

Talking of all this hp amd watts, Im building a 3phase generator using a Nissan Micra engine. The aim is to get about 25amps per phase @ 240 volts :>

Ed

Thats how they are done on my graph, and they do pass at 5252.

Ed

Then unsub from this NG or set up a kill file using the word Saxo. An inane reply like that isn't going to change anything...

BHP is only used in the UK and refers to power measured on a dynamometer. Pre-war British cars were taxed on basis of how much "horsepower" they produced, but this horsepower was calculated and had no relation to actual output - typical bureaucratic nonsense.

still i prefer my inane replies to your inane jokes.