Project, 125mm/5" DSR2 open system

[dvawolk]

Hi, all!

In the following weeks I will build the DSR2 open system for heating requirements.
It will be maid from 3cm thick chamote boards and 3cm thick vermiculite boards.

It will be put inside the 200L drums, which will be 5/3 high (one full drum + 2/3 of a second drum on top of the first one). This will be the ISA of 2,7 square meters (without floor and without the DSR2 burner). Based on calculator it should run reliably on up to 3,67 square meters of ISA.

This will be coupled to 130mm metal vertical chimney pipe, uninsulated, 3 meters in height.

The DSR2 burner dimensions are calculated with:
DSR2 open system dimensions

Compared to Peter's sketch (Sketch DSR2 open) (i scaled the sketch using the "Scale" tool in Sketchup) it looks fine.
Below is the 2D sketch.


Inside of the burner is chamote board 3cm thick (yellow).
Outside of the burner is vermiculite board 3cm thick (yellow).
The green part is chamote board 4cm thick.
Stumbling block is also chamote (blue).

Stumbling block is added in the middle of the upper box length.
Exit port is added in the first quarter of the upper box length.

Exit port goes through 6,0cm thick wall (ceiling). Is this still okay or should it be thinner?

I am open to suggestions, ideas, concerns...

Have a nice day,
Klemen

[foxtatic]

Your open system core build is very similar to my own build: donkey32.proboards.com/thread/3735/sherman-tank-dsr2-rocket-heater (or rather, my humble interpretation of Peter van den Bergs design.)

One big issue I had that it still needs a "door" even though it's an open system. It needs SOME restriction on the open front of the firebox to burn well and prevent smoke back. I explored that issue on Permies here: permies.com/t/152831/Open-System-DSR-Smoke
The door needs to cover 50% to 60% of the firebox opening.

Your hottest temperatures will be inside the "stub" (area right behind the port where the flames mix and heat goes up) so you might consider using your best rated materials there too if you aren't already. I do not suspect the thickness of the exit port will matter.

[dvawolk]

Hi, Foxtatic,

thanks for reply. I found your thread just after i have started mine. Yes, it is a similar thing.
I also checked the Peter's thread and i am familiar with partial door (as opposed to open) system. Peter stated that wire mesh alone already reduces air intake to 60% compared to totally open door. After that this is further reduced with metal plate. Thanks for pointing this out.

After you added the partial closing of firebox - is the smoking problem reduced or eliminated? What is the ISA of your metal container?
Your system is 150mm, right?


Have a nice day,
Klemen

[foxtatic]

Yes, my smoking problem was eliminated after adding the partial closing.
The core I built is actually 180mm and the ISA of the tank is 5.2 square meters.

Somewhere deep in a discussion on ISA, I read that an all metal bell can have a 20% smaller ISA than a masonry bell because metal releases heat faster.
I chose this size core because it fit with the the welds on the tank and the ISA of the tank was almost perfect too.

[dvawolk]

Oh, well. Things change in life - this project ended even before it started. Maybe someday in the future