A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
God of procrastination https://www.youtube.com/watch?v=q1EoT9sedqY
Chris Kott wrote:Sounds like cavitation caused by lack of airflow, especially as how it went away when you closed the door. Was there suction when you opened/closed it?
-CK
Satamax Antone wrote:To me, you must have a restriction somewhere downwards from the batch box port, not air inlet. I can see the flames coming back out the primary air.
Try to load less little wood, more like 3 4 inches logs, or splits. If it carries on. Check your gaps and the transition plenum area. Then the bench or bell etc.
https://permies.com/t/61657/Flue-exhaust-transition-plenum-pictures
bob day wrote:It's tough to say if your exhaust is constricted or not just by matching the riser size to exhaust manifold. I just read a fairly complicated formula and explanation that talked about stream flow or some such, that pretty much excluded portions of some manifolds from being active in free transmission of exhaust. The net takeaway was that under certain circumstance you might need a manifold with three times the area of the riser cross section.
God of procrastination https://www.youtube.com/watch?v=q1EoT9sedqY
Chris Kott wrote:Sounds like cavitation caused by lack of airflow, especially as how it went away when you closed the door. Was there suction when you opened/closed it?
-CK
bob day wrote:
I'm guessing you are counting on the natural cooling of the gasses to provide the movement in that second downward "bell" and doubtless you have your reasons why you didn't build one large bell to allow for a freer stratification, rather than keeping all those little exhaust molecules lock step marching along whether they want to or not.
It does look like the exhaust openings are large enough so let us know how it works out after everything dries out and you solve your air intake.
bob day wrote:I think the thing is that right now your only "complaints" are the pulsations and lack of heat to the bench.
bob day wrote:
I hope this isn't in the middle of your living room with your wife asking when will it be finished?![]()
bob day wrote:
The thermal wool will reduce cooling, and lessen the push of the exhaust out of the bell, adding mass could have its own set of challenges.
bob day wrote:
Just to be clear however, I'm a newbie to these manipulations, and right now I'm just getting acquainted with some of the issues of batch burners. So I am likely not the best reference.
God of procrastination https://www.youtube.com/watch?v=q1EoT9sedqY
God of procrastination https://www.youtube.com/watch?v=q1EoT9sedqY
bob day wrote:Have you noticed that smoke before, or is this the first time you looked at it?
Could that still be from drying the thing out?
taking a longer time to warm up?
what do you think about what's happening?
Satamax Antone wrote:Myself, i would enlarge the 8x8 next to the cleanout. And remove that fin thing.
A human being should be able to change a diaper, plan an invasion, butcher a hog, conn a ship, design a building, write a sonnet, balance accounts, build a wall, set a bone, comfort the dying, take orders, give orders, cooperate, act alone, solve equations, analyze a new problem, pitch manure, program a computer, cook a tasty meal, fight efficiently, die gallantly. Specialization is for insects.
-Robert A. Heinlein
Chris Kott wrote:It sounds like some kind of internal turbulence creating a choke point. If I am understanding it right, its like the back end of the system is working so well when it gets heated up that it's creating vacuum inside because it is trying to draw more than the intake will allow. The vacuum pulls as long as it lasts, then it breaks as the vacuum gains purchase on the incoming air mass, which is then strangled into vacuum as the system tries to pull all that air out of the system, hence that pulsation, or cavitation. The vacuum pockets are like air bubbles forming in the motion of a propeller underwater.
-CK
Chris Kott wrote:
I think you need to be able to vary the amount of air going in better than you can now. The fact that cracking the door a bit helps just proves this, I think.
-CK