Sarfraz Munir

I found the answer I was looking for my biggest concern was around the way that heat moves up and down so I found the answer in another post. Im going to stick to metal but use silicon carbide on the exhust  

"The barrel is metal for a reason. The radiant heat loss that the gasses undergo (by transfering heat to the air of the room) lowers the temprature and drives the downward "push" that alows the rocket to fuction. If you use a material that insulates or has thermal mass you will kill the rocket. That is also why your heat riser needs to be very insulative (no thermal mass): To keep the temperature differential between the upward and downward moving gasses".

To answer your question around the material

High aluminum Ceramic cement is a Ultra-high-temperature ceramics (UHTCs) are a class of refractory ceramics that offer excellent stability at temperatures exceeding 2000 °C

I can get hold of Silicon Carbide in a cement form which can then be mixed and molded into any mold or shape. I was thinking about the ECO Stove which uses this technology as per video below

Hi

I'm planning a rocket stove and just need some help?

I’m building a 6 inch system for my workshop, using refractory material for the burn chamber and riser with a secondary air introduced at the bottom of the riser.

I was thinking instead of using a drum on top of the heat riser why not use a thermal mass conducting material like Aluminum or Silicon carbide or even a mixture of these with an Insulating Castable product or even clay?

As the heat exits the tube it heats up the thermal mass so you have more of an even heat output. so it would be like a masonry stove or (A rocket stove masonry stove).

Is there a reason why this has not been done before?

Am i going in the wrong direction with this and should I just stick to a barrel?