is a barrel necessary for an outdoor bench? i mean could you just have pipe coming off the top of the riser, and going down and into a mass bench? am i missing an important function of the barrel besides giving off fast heat?
The hot gasses cooling in the barrel helps them sink into the bench/flue. If you keep the firebox low you could just use enough riser to reach up to the bench.
Without extracting heat, downflow is a draft liability.
