Thomas Holm wrote:It is 2m up so no oven, it is a bit too high up. 😁
Thomas Holm wrote:What kind of slab/stone do you use Satamax? Havent really thought about it that way but it will probably work just great. 😁
Peter van den Berg wrote:As I see it, your steel bell is 4 times system size
Thomas Holm wrote:The are a few pictures and doodles at the first page of this thread, maybe that can make it easier to see how it's done.
Also, it has always (a few, maybe 5 burns in total, only small burns) produced a light white smoke that dissapears a meter from the chimney, not at a forced flow but very dreamy if that explains it's behavior.
Thank you so much for commenting, I need the support and somewhat fear the large undertaking i feel might be needed to make it work.
Peter van den Berg wrote:The biggest blooper I am aware of now is the p-channel. Actually it is neither a floor channel or p-channel since it ends in the middle of the riser. So there's some explanation to do.
The vertical stub of the floor channel should be about 5% of riser csa, square and reaching to about half the port's height. Size for a 200 mm system should be about 40x40mm internally.
Situated just in front of the port, not behind. The horizontal part, the feed, should be twice as large as the stub, so for this one could use two ducts side by side, the same size as the stub.
Every object inside or behind the port will cause the thing to produce black smoke. What exactly this is caused by remains unclear, presumably something to do with disturbing the double vortex at that spot.
The above is the most likely cause of not performing to specs. I am quite puzzled why you did it like this, the batchrocket site is quite clear about this particular point. This batchrocket design is what we call "a tight design", change something it doesn't matter what, and it won't do what it says on the tin.
My advise: rip out that channel, build and install a proper one exactly to specs and it will work. Whether or not as a result the pulse behaviour will be gone can only be tried.
And oh yes, the port at 65 mm is a bit too narrow, this should be 72 mm or very close.
Satamax Antone wrote:Thomas, even with the bypass open? All the joints, welded or covered?
There is one thing. I find the port extremely wide compared to the firebox's width!
The black smoke and the smell is confusing me. I guess it is poor combustion from poor flow?
Another thing. May be your plunger tube is too low in the half barrel.
Your barrel to bench transition, doesn't seem that bad to me!
Satamax Antone wrote:Well. Daft question. Are those pieces of ceramic board well stuck to the firebox's edge? What depth are these?
If anything over 5cm deep. That's no good.
Re checking your plunger tube. It seems awfully low. You say 8 cm?
Satamax Antone wrote:re checking your pics. The funnel at the end of the plunger tube is very flat flared. It seems more than 5cm width for 5 cm height. (45°) So this might well be a problem.
If you've chosen 8 cm gap. That means that with a X3 the CSA That would mean 37.5 cm outer circumference of the funnel. Am i far?
Let's assume the height of the cone is 5cm.
20cm X PI 62.83
62.83 x 13 =816.814 cm².
If the funnel edge is 37.5cm diameter, So 117.80 cm circumference. X the gap of 8cm. 942.47cm² Which is the X3 CSA i have used to guesstimate.
Your 20cm pipe's circumference, multiplied by the gap (estimated) of 13cm makes 816.814cm², so less than recommended ( by Peter) X3 CSA minimum
(well, remember that this is from the top of my rotten head)
Yes i know, i said earlier you could may be get by with 1.5 times CSA. I guess i'm wrong.
But you see my point above. Funnel too shallow. ney working. Imho. Raise that bleeming edge to 10cm!
then i'll come to the other point. Or points.
Satamax Antone wrote:Well.
About the chimney?
What is your width and depth at the red line?
Then, have you filled above the half barrel bell? If not, may be putting coton covers on it, to raise the temp could help. Your temps outside are not cold enough yet to drive a big stack effect. I guess you haven't warmed up the chimney before.
If the transition from 20cm tube, to the chimney is bad, i think i can offer a solution.
Satamax Antone wrote:Well, since you need to raise that pipe with the funnel.
What i would do, is make a cutout of the width of the of the inside of the chimney; in the face they are jointing with the tube. About 60,70 cm high. Or whatever is needed. And rebuild a little wall against your chimney, to have a better transition area there.
If you see what i mean. That would shorten your pipe entering the chimney of the width of a brick.
And also, do you have a photo taken from the top of the riser looking down into your first transition area? It doesn't seem too bad to me. But what do i know.
Satamax Antone wrote:Also, if you do that little wall. Make a little door above or bellow your tube, to have a cleanout there. You won't be sorry.
And, there is a trick you could use, temporarily, to heat up your chimney. Make a bypasss from your big horizontal cleanout, to your horizontal tube cleanout.
Satamax Antone wrote:You pictured the same as this?