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height of chimney affecting gas fired reduction results. a little

updated tue 2 mar 04


Craig Dunn Clark on mon 1 mar 04

hazy on this one

I did not have a firm grip on this concept before and I am still a bit hazy.
Is my understanding correct when I say that as the gas is heated and becomes
less dense the force of gravity relative to the mass of heated gas and the
earth is less than the force of gravity relative to the mass of cooler gas
and the earth. As a result the cooler, denser gas is "drawn" downward
thereby displacing the hotter gas in the stack. Is it advantageuos to look
at this an extrusion of sorts or am I getting it wrong?
Craig Dunn Clark
619 East 11 1/2 st
Houston, Texas 77008

----- Original Message -----
From: "Ivor and Olive Lewis"
Sent: Saturday, February 28, 2004 9:42 PM
Subject: Re: height of chimney affecting gas fired reduction results

> Dear Bruce,
> To increase the Volume of the balloon you have to increase the
> pressure. The volume of the interior of the chimney does not change.
> I understand fully that it is Gravity acting on density differential
> that drives the process forcing hot gas up the stack.
> Doubling the altitude of the stack does not alter either the density
> of the cold air or the density of the hot gases. The motive force
> (PE=mg) is constant.
> Best regards,
> Ivor Lewis. Redhill, South Australia
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