chimney right above the fire to burn up the smoke and speed up the draft.
Heat and burn the tips of the sticks as they enter the fire to make flame, not smoke.
High and low heat are created by how many sticks are pushed into the fire.
Maintain a good fast draft from under the fire, up through the coals. Avoid allowing too much extra air in above the fire to cool it.
Too little draft being pulled into the fire will result in smoke and excess charcoal.
Keep unrestricted airflow by maintaining constant cross sectional area through the stove. The opening into the fire, the size of the spaces within the stove through which hot air flows, and the chimney should all be about the same size.
Use a grate under the fire.
Insulate the heat flow path, both around the fire.to and the pots or griddle.
Maximize heat transfer to the pot with properly sized gaps.
LINKS:
Design Principles for Wood Burning Cookstoves (pdf)
