rocket drum can i use a car exhaust ?

i have a blue oil drum i want to make a burner fo rmy allotment garden, riff raff,

i was going to simply cut a square door on the side, hinge it on and add an airflow slot to slide.

then i have an exhaust about 2inch wide that fits into the already there fill hole in the top of the drum and weld it down,
its a straight through exhaust


this hole on top red cap https://upload.wikimedia.org/wikipedia/commons/0/07/Drum_%28container%29.jpg



like this

What you are describing doesn't sound like any kind of rocket combustion unit. To get the combustion efficiency and heat output of a rocket stove, you need specific geometry (there are several proven styles) and an insulated combustion zone. Even if you are just mainly wanting a burner to get rid of waste biomass, you would want to burn it completely and not generate pollution. (There is another important point of why you would burn biomass instead of composting or otherwise turning it directly into improving your soil.)

A regular exhaust pipe or muffler would not allow enough flow for a fire similar to your picture to burn well - one principle of rocket stoves is that the cross sectional area is relatively constant throughout the stream. You need fast enough flow after the initial combustion point that the gases experience turbulent mixing, and all the fuel gases can meet oxygen and burn.

https://permies.com/t/41635/Top-Questions-Rocket-Mass-Heaters

http://donkey32.proboards.com/thread/1170/tube-dimensions

Glenn Herbert wrote:What you are describing doesn't sound like any kind of rocket combustion unit. To get the combustion efficiency and heat output of a rocket stove, you need specific geometry (there are several proven styles) and an insulated combustion zone. Even if you are just mainly wanting a burner to get rid of waste biomass, you would want to burn it completely and not generate pollution. (There is another important point of why you would burn biomass instead of composting or otherwise turning it directly into improving your soil.)

A regular exhaust pipe or muffler would not allow enough flow for a fire similar to your picture to burn well - one principle of rocket stoves is that the cross sectional area is relatively constant throughout the stream. You need fast enough flow after the initial combustion point that the gases experience turbulent mixing, and all the fuel gases can meet oxygen and burn.

https://permies.com/t/41635/Top-Questions-Rocket-Mass-Heaters

http://donkey32.proboards.com/thread/1170/tube-dimensions

cool i see, and i understand, i dont have somuch $$ at my hands and just want to burn my allotment waste, reason it was overgrown with horrid seed grass so every seed grows i wana burn em off this time, and keep burning them we also have meres tail that breeds liek hell

i was hoping of making my burner safe as to not burn all the bushes and dry grass around like a normal burning bin will..

any ideaS? im a welder

If you hot compost it the seeds will be killed off. If your just looking for a burn pit just cut the top off a 45 gal drum and drill a few holes in the bottom. If you want to get fancier old propane tanks or fuel tanks with atleast 8 inch exhast. But this isnt a rocket stove.

For fast and complete burning, a pocket rocket should do the trick. A standard barrel and a couple of lengths of stovepipe is all you need.