Hey, all.. A few days ago, Canyon came to visit and he brought his ideas with him. ;D In my shop, we put together a six inch, horizontal feed test. We slapped it together with scrap-crap, brick and mud. It was NO candidate for a beauty pageant, but it SURE DID WORK!
(grr.. Having trouble with the website, so I'll use the attachment feature )
Last Edit: Jan 25, 2014 7:40:35 GMT -8 by peterberg: found missing picture
The key to the works is the air intake needs to be reduced to 1/4 system size and back at the throat, it returns to system size (or a little bit less) just before the heat riser. The brick at the top, (shown in the picture) drops down below arch height. Like Peterberg's rocket siphon. We used a trip wire brick there.
Last Edit: Jan 25, 2014 7:42:02 GMT -8 by peterberg: found missing picture
Believe it or not, we ALSO figured out that the Peter-Channel REALLY WORKS in this setup.. We placed it just in front of the brick I was talking about above.. The channel is sized for a "regulation" six inch system. Canyon carved out two channels to draw air over the top of the arch (for pre-heating) and into the peter-channel, these channels were covered with brick and open to the front of the stove.
Last Edit: Jan 25, 2014 7:46:16 GMT -8 by peterberg
It took a while to get my head around it, but now I see what has been done. It looks like the same principles as my rocket syphon, the new part is the implementation of the P-channel in this. It is leaning on the assumption that the majority of the combustible gases are in the top segment of the tunnel/firebox or whatever. The surprising part is this: in spite of the primary air coming into the front side, this setup didn't smoke. The whole thing is inside the workshop, and that would be impossible with a smokey fire. Is this correct?
The firebox looks like 3 times as large as system size, the riser twice as long as the firebox. Am I right? The next question will be: how will this new "thing" behave, completed with barrel and all? And you'll need a door of some sort.
This could be a next step towards a simple and very adequate rocket heater variant.
Edit: Some more questions did spring to mind. Is the "thing" loaded full as a batch-fed device? Is it lit in front or close to the riser? Are there results from canyon's analyzer? How many minutes to smoke-less burning started from cold?
Last Edit: May 2, 2012 10:16:59 GMT -8 by peterberg
The riser was what we had laying about. It seemed over-tall to me and we spent no time experimenting with riser height.. Ideal riser height is still at question. We did load it as a batch feed. We lit a small fire, shoved it all the way to the front and loaded up behind. Peter, your rocket siphon is a large inspiration for this stove. I think an improvement would be to make the firebox floor into a V shape so that the wood is forced together as it burns. As it was, the fire would burn down and it would disarrange, not burning as cleanly as it could.
We ran (started) the stove twice, the first time it took some time to get up to temperature and burn cleanly. The main issue was finding out how much air to allow, once the opening was set, it ran fine. Also, the first run started without the Peter-Channel. After some fiddling, we took the stove apart, added the channel, rebuilt it and stoked it up again at which time it took off so fast that flames shot out of the top of the riser. We had to screw some cement board to the shop ceiling to protect it. After a little time, we placed a small, 16 gallon barrel over the riser to protect the ceiling.. The next morning, we started the stove again to warm our hands before taking it apart. It was up to clean burning VERY quickly. I think the combination of the siphon, tripwire brick and channel are the winners here. Obviously, there is some work to be done on this design to perfect it, but I'm quite impressed with the promise it shows. Something like this will be relatively easy to build, provide a larger firebox for batch loading, allow for a glass door to see the fire, etc.
Oh.. Peter, Canyon opened up the analyzer and took it out.. We oohed and ahhed over it for a bit, intended to use it and got so wrapped up in the new stove build and rebuild that we completely forgot to use the analizer..
Peter.. I forgot to say that the workshop has no doors or windows. The shop is currently WIDE open, I plan to close it in this year, add doors and windows.. During the summer months our forest is a tinderbox, it's not a question of IF someday it will all burn but WHEN. I don't want to be the guy that sets it all to light, so It's a non-flammable, cob metalshop. A safe place to put the forge and welding rig. During the first burn, we smoked the place up pretty well getting the stove started and figuring out the air size, etc. It was raining so we needed a place out of the rain and the shop was it.
(edit) once we got the air right and the P-channel in, it stopped smoking. The second run did not smoke at all.
Here is a Sketchup file of our brick layout. Our arch was NOT as high as what is shown in the .skp file.. Also, when I made this file, I didn't bother to get the size of the Peter-Channel or the tripwire brick correct. Really, this is only to show the layout of the parts more clearly than our images provide.
Umm.. I checked the size of the P-plate against the sketchup model.. It's actually pretty accurate. The difference being that in the model, the plate has no thickness.
Also, the position of the plate in the model is a little off. If you hide the arch groups, you will see that the plate inter-penetrates the bricks below. Clearly, it ain't that way in reality. The arch bricks needed to be cheated forward slightly to accept the plate. When we did that in reality, we collapsed the arches and so the quick rebuild.
OK then... Thanks for the drawing, this is quite clear. The firebox is remarkable large for a first iteration, something between 4 and 5 times system size.
Lately, I've come to the conclusion a lot of the ballast gases (the 79% of air that doesn't contribute to combustion) pass through at the bottom of the siphon or burn tunnel, while the combustible gases like CO and tars are at the top. The opening has to have some height also, a narrow horizontal slit won't work, I've tried that before. Following that assumption, the only thing that need to be done is adding some air at the top. That could be the main reason why the P-channel is so effective.
Looking at your drawing, having the opening from firebox to riser vertical instead of horizontal would also be right in this respect. With the siphon opening horizontal, there's a stiff chance some unburned stuff could escape through when not the whole width is filled with flames.
I'd need to build a test bed this summer and let the Testo have a sniff at it. Too bad you both forgot about the analyzer, but there have been made some choices which make sense theoretically. This has been time well spent, gentlemen!
Hmm.. So, in light of your "tile shaped roof", that would make sense. Burnables will be forced up into the narrow shape, where they would be more likely to contact flame.
One conversation that Canyon and I had.. Metal heat risers burn out. Metal can only burn if there's enough oxygen left over to do the job. Is there some way to reduce or exclude excess oxy (and other ballast gases)?? I know that is the intent of the Russian bell stove builder with his narrow slot at the bottom of the burn area. You and I have spoken about this in the past, you seemed to say that it makes no difference.. I still wonder if a way can be found to shunt that stuff out of the system.. ??
dan1941300: If possible in metric cm, how many Celsius at the chimney? Is there anything you would do different if building again? Sorry for my bad english, my language is german, austrian. thx a lot
May 11, 2018 9:38:02 GMT -8
smarty: Dan my batchbox reached 1150C so refractory cement rated to at least 1200C
May 21, 2018 22:53:56 GMT -8
mercedes: Not sure where this question will end up...I just registered. HOW THICK SHOULD PERLITE/VERMICULATE/CLAY INSULATION BE BEHIND THE THERMAL BATTERY/COB BENCH IF IT BACKS UP TO A STRAW BALE WALL? Thanks! Can you please also post me: firstname.lastname@example.org thnx!!
May 28, 2018 20:05:23 GMT -8
kkp: Mercedes: Benches don't get real hot. In fact, they are rather cool compared to other areas. You shouldn't need a mix like you described
Jun 7, 2018 18:10:52 GMT -8
maartenmartens: beste Peter, ik heb je eergisteren een mail gestuurd via het contact formulier op je website , heb je die goed ontvangen ? mvg Maarten Martens, architect - geobioloog (mail betreffende de bouw van onze eigen RMH)
Jun 20, 2018 13:21:57 GMT -8
martinm: any one here with info \ experience with heat (from a mass heater) distribution with ducts throughout two storey house ?
Sept 8, 2018 22:58:52 GMT -8
padica: Good morning, this is a wonderful subject, please someone can help me with the theme of double and triple combustion, how it is achieved, theory and design, thank you
Sept 15, 2018 7:13:40 GMT -8
wiscojames: I'm afraid you won't get a response to such a vague question - I suggest reading through some of the threads related to your questions before asking for an explanation. People will be very generous with their knowledge if your question is more specific.
Sept 18, 2018 4:48:00 GMT -8
daniel: in my experience as I am working now on something of that nature, I have thought of making a heat exchanger and distributing the heat through vents using a slower fan. Now after a few years I realize that mass heaters give out primarily radiant heat, for
Nov 30, 2018 12:48:38 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place...
Dec 16, 2018 18:10:49 GMT -8
vesuvius: High Temperature Glass options,
Jan 4, 2019 16:28:17 GMT -8
vesuvius: Do any of you have experience with using the glass from home oven doors on a rocket stove? I'd like to have a viewing port on my stove but don't want to fork out for new ceramic glass. Any thought as to whether it would take the heat of a rocket stove?
Jan 4, 2019 16:30:40 GMT -8
yaya: you dont need the blowair for that temp..
Jan 13, 2019 16:43:57 GMT -8
flybywire: Glass window from an old washing machine is designed to take high temps. Cheap solution to your need.
Jan 27, 2019 0:10:58 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place to have a discussion... it is for short announcements
Feb 7, 2019 0:11:23 GMT -8
coastalrocketeer: you won’t likely get replies to questions here, and it is not a spot that makes holding an ongoing discussion possible...
Feb 7, 2019 0:12:22 GMT -8