I had a large piece of a hollow log and set a fire inside it. It worked incredibly well... too good in fact! It was so violent I had to take the wood out from inside. It was amazing to watch how the fire fed itself, even from drawing in smoke from pieces of burning wood outside of the log, and the wild vortex it eventually created inside. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-NMlTT6sfrG8.htmlsi=IiCJaVMbnEpkXPgg
Another concept with a twist. It looks like a fun one for sure. If the chimney/firebox connection was more "air tight" it would help, but there is so much outside air getting drawn in through the openings, it almost chokes the chimney effect.
I had to watch this one again, and I'm still laughing at this design! Also I didn't expect it would work nearly as well as it does. It's actually quite an entertaining flame pattern.
Quick and easy to produce this model. You are making good use of the "corrugated" shape for the liner to channel air both up and down. I had to watch this again to see if I had missed something that was producing the secondary combustion flames. This simple layout worked amazingly well.
It was a very impressive and aggressive fire! If you only load wood in through the top of the chimney, is the flame more controlled? Effective for a simple design.