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Re: F.I. Tech (was BSFC)

To: Jim Dincau <jdincau@qnet.com>
Subject: Re: F.I. Tech (was BSFC)
From: Dave Dahlgren <ddahlgren@snet.net>
Date: Wed, 24 Sep 2003 03:38:21 -0400
To be honest i was thinking about that scenario while i was typing the previous
message. There probably is a point where it could get too fine if it would stay
that way. Also explosions all have a time constant to them, they are not
instantaneous. When you burn fuel in an IC engine there are some pretty small
time constants as well. To keep the math simple at 6000 rpm there are 20
milliseconds in a complete cycle of 720 degrees but you only have 180 or less to
get the energy out of the fuel or 5 milliseconds at 6000 rpm.Of course the
higher you go in RPM the less time you have and most race engines run past 6000
rpm. While this is all interesting i guess the final thought i have is that I
have no clue if it works the same as coal dust at all as i know very little
about coal dust in general. but i do know there is not very much time to convert
the fuel to energy.
Dave

Jim Dincau wrote:
> 
> Do liquids ever get into the same problem as solids? As in the flame front
> in coal dust expanding so rapidly it ends up as an explosion?
> Jim
> 
> > Dave said: Think of what we are trying to do here. We are burning the
> fuel..
> > With finer drops you have more surface area. As rpm goes up the drops have
> > to be finer or you will be passing a lot of unburned fuel through the
> > engine.





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