Topic starter
29/03/2011 4:10 am
Is it feasible to convert a steam engine to work from compressed air, and, only have a small boiler to operate the whistle and calliope?
29/03/2011 6:22 am
Kevin:
A engine made to run on steam, will run on compressed air without any conversion..
But Air and Steam have totally different properties and expansions with heat/Steam, that don't occur with air...
As for the Whistle & CaLLiope , I got both for Sale , And a Boiler too.. lol
29/03/2011 12:14 pm
You'd have a hell of a time running on air, look up enthalpy, you'd end up burning more fuel trying to get an air compressor big enough to push along a boat (think of all the heat that is generated when compressing air). Another note to consider is lubrication of the cylinders, pushing in dry air is the same as running your car without oil. As long as it's just a little engine, theres not much problem, but you start putting a load onto it for prolonged periods of time, you want steam, you don't see any major power plants or aircraft carriers running on compressed air.
29/03/2011 4:00 pm
High pressure air, as it expands, cools. The cooling then further reduces the air pressure, so during a piston stroke the force declines dramatically. Steam contains greater heat energy within the water vapor. As the steam expands, the water vapor actually flashes into steam, counter acting the pressure drop. So, steam has a slower pressure drop curve in a cylinder than air. Steam provides a stronger piston stroke overall than air, which declines rapidly after the first few inches of movement.