[Stoves] RE: Henson Center Fiure Burner System; Was: Re: improving charcoal stoves

[AJH]

On Sat, 10 Jun 2006 10:26:19 +0200, Crispin Pemberton-Pigott wrote:

>Unlike a spark plug which must fire at a certain time, the flame is always required so it will be better in principle to have a continuous ignition source such as a hot wire.

I wonder what the effect of the hot wire is, is it an ignition source
or a means of holding the flame or is it catalysing a reaction? It has
to be above the spontaneous heat of combustion of a component of the
offgas to supply enough energy in the absence of a flame but if it
stabilises or maintains a flame then this serves the purpose also.

>As the wire conducts heat at about 1/2 the rate of mild steel, it tends to remain hot for twice as long, meaning you will see it glow brightly for twice as long after a flame has been on it.  The CO gas tends to get pushed around by the random motion of the fire so your chances of getting it lit are better when the wire stays hotter longer.

This makes sense to me, the wire acts as a sort of high temperature
buffer between variable flows of gases, in which the gas:air ratio
moves out of the envelope which will support a flame.
>
>The larger the wire diameter, the more heat is stored and the more expensive it is, and the longer it will last.
>
>Inconel and nichrome wire is also available (www.kanthal.com ?) but these products are made either from 'unaffordium' or 'unobtanium'.

I source high temperature wires by taking them from the electric
heating elements in radiant,storage heaters and around the drums of
broken tumble dryers. Possibly not available in hotter, poorer
countries.
AJH