That's a good link. As I say, I want to construct one with a taller chimney, to see if the extra height will help improve combustion.

I am thinking that the diameter of the holes needs to be minimized as well, to aid with vortexing the draft and also improve the combustion process.

I'll have to give this a try sometime. If it works, then I won't have to worry about packing any sort of portable rocket stove all the time.