[Stoves] iCan Trash Can Style - very clean burning

[Crispin Pemberton-Pigott]

Dear Friends

 

This is a noteworthy and clean burn.

 

Please note everyone, that operating the burner inside the can greatly
changes the performance characteristics because the burner is heating the
air inside.

 

The air, in order to reach the bottom, must pass through the heating zone,
and it resists the downward passage.

 

Because the gap between the can and the burner is large, there will be a
great deal of air entering and leaving again taking heat with it, but there
is still an effect. If the burner is placed outside the can in a windless
location, the performance will not be the same. 

 

Similarly, if the can was only say, 30mm larger in diameter than the burner,
there would be much more preheating because the airflow in and out would be
greatly limited. In that arrangement, the total height of the preheater
would have to be reduced to about 50% of the total height of the hot gas
column. If you make the two the same height, there is a serious interference
in the air flow, especially for secondary air and it may not work well at
all. The sweet spot is located using a gas analyser on the emerging gas
stream, with a target of 80-120% EA as the target. That means the O2 level
would be 9-12% by volume (about 105,000 ppm ±15,000).

 

The fact that no flames were seen emerging from the unit indicates that the
flame space above the secondary air injection point is about right. Smoke
being invisible doesn’t mean there is no smoke – it means it is so good to
find some you have to get a particle counter.

 

Regards

Crispin

 

 

iCan in its trash can.  It would look like this in full operation also.

They only evidence that it is operating is a shimmering column of very hot
air.

No steam is seen as exhaust gases are several hundred degrees above the
boiling point.

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