[Stoves] TLUD-ND transition from hydrocarbon flame to charcoalflame / Temperature gap between self incending charcoal and woodgas

[Boll, Martin Dr.]

Kirk, Crispin and all,

by time I got aware that the different self-incending temperature of charcoal and woodgas makes a lot of problems in burning wood, especially in avoiding smoke.

All burning of any stuff takes only place above the special self-incending temperature. It does not work under that tmperature. - So simple, but was not aware of.

Guess charcoal about 600°C, guess woodgas about 1200°C. It does not matter if not exactely. There is enough temperature-difference to make trouble; - we all know  :-)

Charcoal burns ( and continues burning) still by small draft with dark-red colour.
To incend woodgas, charcoal has to have yellow- or white-glow. What draft-speed is necessary??
(key-word: Superficial speed ??)
In contrary to that pretty quick draft-speed, wood-gas has a very slow flame-speed. - Crispin I remind, that we talked about the tremendous low flame-speeds of different air-woodgas mixtures off stoves-list a lot of time ago.

The draft, making a bright charcoal-glow is fast enough to blow off a woodgas-flame!! I am sure you know that, as I saw long before understanding why.
I remind the ancient method of fire-starting: Glowing charcoal within a light "soft-ball" of dry grass or staw.
Blown by mouth, to make smoke and then fire. There is quick and slow moving air close together, so that the yellow-blown charcoal-glow incends the gas-flame, which gets not so fast blow to be blown off.
- My greatest respect to our ancestors for their knowledge, art and practise! 

Another important fact, as well respected by that old method of fire-staring,  is radiation and reflection of heat.
A small flame from a twig or leaf needs a same flame from another  twig to be heated by its radiation,  because the small flames loose so much heat by radiation. The small flame does not produce enough heat to maintain outgassing _and_ holding the self-ignition temperature of that woodgas, which is necessary to continue the burning.
 - My conclusion since I understood this: I incend with a match always two or three small flames, burning close together. - A candle is another system than wood-burning.

I made some simplest experiments with just matches. After incening a match held it in different inclination-angles. (The match contains some wax and is not a mini-log!) 
A small wood-spoon, from leaf-wood, shows the differences by different angles clearer.


Kind Regards
Martin