Hi Day
On (14 Nov 97) Day Brown wrote to Jim Dunmyer...
 JD> That, and you can store much more energy in a high-speed  
 JD> wheel, even if it's lightweight, than in a low-speed, heavy  
 JD> flywheel. I've seen the formulas, and it's fairly dramatic. 
 DB> But, I do not see how to get a vacuum to put the flywheel in,
A vacuum is a problem- how to raise it, then how to maintain it.
Large central station generators save a huge amount of energy, by
reducing the windage loss thru filling the generator case with hydrogen
gas. Hydrogen having such a low density there are very few molecules dancing
about, even when pressurised. No doubt Helium would be an alternative but 
ess
effective.
The first such machines [c1940?] used low gas pressure and leakage was no
problem. Modern machines run at about 40psi I think, so make- up gas is piped
in to make good the inevitable leakage, the slight loss being thru bearings.
The oil supply is delivered at a higher pressure than the gas pressure, so
there is a [drained] oil leakage into the casing rather than a serious gas
leakage outward. There is also a gas seal at each bearing, and the sealing 
il
system is somehow divorced from the lube oil system. The seal oil having
degassing feature and gas monitoring.
But you mightn't want to drive an auto with hydrogen on board, even tho you
now carry lotsa flammable, explosive gasoline!!
Cheers......ALEC
... ......Many people die of thirst but the Irish are born with one 
illigan]
--- PPoint 1.92
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