ARC E-Newsletter 9/10/25: Cleaning Up Combustion: TOO COLD!
Aprovecho Research Center
Cleaning Up Combustion: TOO COLD!
In the middle of August, we had three stoves under development using the three emission hoods (two-forced draft, one natural draft). Sam and Travis built the natural draft hood to help improve heating stoves. Sam is thinking about making another one, number four, since we are working on more heating stoves and things can get a bit backed up.
During testing teams often trade observations during the day and sometimes, when the air temperature gets a bit elevated, I’ve heard folks exclaim: “WOW, FIRE HOT!”
What makes fire colder? Things like:
- The air entering the combustion chamber (~30C in August)
- Surfaces that absorb heat, like thermal mass or
- Pots of water (~100C)
Thermometers are very helpful when trying to improve performance! Both combustion and heat transfer efficiency increase when temperatures rise. Taking a stove’s temperature(s) can facilitate making helpful changes in a prototype.
WOW, look at the temperature, IT’S HOT!
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