[Stoves] [Ethos] Fwd: Re: Fuel Efficient Stove Programs in IDP Settings- Summary Evaluation Report, Uganda

[David G. LeVine]

I have been a lurker here and on the gasification lists for a while, and 
there seems to be a potential win by combining both technologies.

A Rocket stove has been reported to give off excess CO.

Three stone fires tend to burn the excess CO and give better efficiency 
due to the small blue flames.

Hypothesis:
A Rocket stove with a heated secondary air supply might be more efficient.

How to test this:
Make a steel can fuel container with limited air from below.  Put it in 
the Rocket chamber and light the fuel.  Restrict the air coming around 
the can until the gases do not fully burn, then increase slowly for best 
heat output.

Why would this work:
Volatile components of the burning biomass vaporize, by using a "tin" 
can the gasses can be contained and protected from dilution which would 
prevent it from burning.  Some heat will go to heating the can, this can 
be used to pull fresh air in and preheat it (cold air is NOT a way to 
enhance efficiency.)  When the gasses combine with the heated air near 
the pot bottom it will burn dumping its heat load closer to the pot 
(again, lower losses due to a controlled burning zone.)  Since the 
losses to the can are not transferred to the outside world, they are 
reduced.  When all volatiles are gone, charcoal remains and can be used 
to keep the pot warm after the initial cook fire goes out.

This is a traditional TLUD burner except it has no fan and it preheats 
the secondary air.

Comments on this (obviously) more complex hypothesis?