NetNews Usenet Archive 1992 #31/NN_1992_31.iso/spool/sci/electron/21282

Internet Message Format | 1992-12-21 | 3.2 KB

Xref: sparky sci.electronics:21282 sci.energy:6315 rec.autos.tech:17000
Path: sparky!uunet!psinntp!ncrlnk!ncratl!mwilson
From: [e-mail] (Mark Wilson)
Newsgroups: sci.electronics,sci.energy,rec.autos.tech
Subject: Re: Flywheel batteries as EV power source
Message-ID: <[e-mail]>
Date: 21 Dec 92 14:23:10 GMT
References: <[e-mail]> <[e-mail]> <[e-mail]> <[e-mail]>
Organization: NCR Engineering and Manufacturing Atlanta -- Atlanta, GA
Lines: 53

In <[e-mail]> [e-mail] (Daniel Rubin) writes:

|OK I agree that cars do not expode like seen on the big screen.  A car
|can expolde though.  Take the above example and add a high amperage electrical
|system and loads of wires to the top of the gallon of gas.  Now if the
|conditions are good the gas will spatter the vapor will come in to contact
|with a spark from two shorting wires and you will get a nice explosion.
|Fuel-Air explosions are quite nasty.  Buring gas will not do that much, but
|produce heat, whereas buring gas vapor mixed with oxygen in the air will
|produce a powerfull explosion...

|Try it.  Drip a few drops of gas in a fire pit or some other similiar type of
|open ended enclosure ( no more than 5 or 10 drops of gas ).  Wait for it to
|vaporize and then throw a match in.  Whooomppp you will feel the shock wave
|and it most likely with scare the sh-eck out of you...

|>You can also try shooting it with a rifle or whatever. I have.
|>It's pretty boring.

|This can cause a rather large gas vapor cloud with the first shot assuming it
|is a high enough power rifle to rupture the container somewhat.  If the
|container is steel and the bullet is steel a second shot should knock your
|socks off...

|>>>Unless you wrap the flywheel in a massive enough container that it can absorb
|>>>all that energy without vaporizing, you're going to have an explosion.
|>>
|>>Why bother, we don't wrap our gas tanks in a container that would contain
|>>their explosion?
|>
|>Because gas tanks don't explode. Movies are not reality.

|Car crashes violently, gas tank is ruptured and gas is forced out of the
|rupture by the crash.  Gas vapor cloud forms rapidly and comes in contact
|with the shorting positive battery post agains the frame of the car.  That
|will cause a rather large explosion and quite a lot of fire.  This would
|be a rare case and the individual would most likely not survive the crash
|itself...

True, fuel-air explosions are nasty things.  And it is possible for some
of the vaporized gasoline to ignite.  The question I believe would be,
What percentage of the gasoline that used to be in the tank takes part in
such an explosion?  I would think that it would be just 1% to 2%, if that
much.  Also how much time does it take for the vapor cloud to form?
Unless the occupants were incapacitated by the crash, they could use that
time to escape.  A flywheel on the other hand would most likely fail on
the moment of impact.

--
Mob rule doesn't become any prettier, just because the mob start to call itself
a government.
It ain't charity if you are using someone else's money.
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