Nice design and use of indigenous materials.

You have a nice rocket stove there, but 90 % of the heat is going up the chimney. If you can narrow the intake a little and stabilize the pot over the chimney exhaust it would boil in 1/3 the time.

The reason it is cleaner burning due to the gas given off by the wood continuing to burn up in the chimney. That's why there is more heat.