The Role Of Oxygen Info
There was some great information in the old forum, posted by the user named Combustion, about burning and oxygen. When I find it, I will post it here.
Until such time as the great information shows up, settle for the good.
To create fire, you must have fuel, air and heat. And, these things must be in proper proportions. Too much of any one will not make for a strong health fire. Heat, in a corn burner is for all intents and purposes, a constant. So lets throw it out and talk about air for a while.
Corn burning does not happen naturally in normal air pressure, as in the case of a wood stove. It requires a forced draft. In a corn stove the forced draft is provided by the draft fan. A draft fan takes what would in normal air be a smoldery, barely burning corn fire and turns it literally into a blow-torch. All draft fans have an air intake adjustment in the form of a swinging door that partially covers the draft fan air intake. By adjusting this door, either more, or less air is sucked into the burn chamber. Generally, this door must be adjusted once each season to the corn you have purchased for the year. But, if you are buying corn in small stocks, many times you will have to adjust the fan several times, maybe with each new lot of corn.
In addition to burn chamber draft, there is also chimney draft which bares talking about. The amount of draft you have going up your chimney influences your furnace efficiency numbers. Too much draft and your heat is passing over your heat exchanger so quickly it never really gets pulled out to be blown into your house. Too little draft and your fire just won't be right. It is being starved for oxygen and will look rather lazy in it's burn.