With my cyclone the gases are introduced at the top side of the syclone. The gases are spining next to the inside wall and spining down wards. My inside exit pipe is about 3 1/2" into the cyclone.
Sorry the pictures are not in order, I did a very bad thing here. JO MIGHT HAVE NOTICED. In the back ground of the picture that I had to remove very quickly was the WK Firetube showing the build of it. It now has a white towel over it. I saw the picture zoomed in on them and Panic! @JO_Olsson did you notice what I did?
Here is where my cyclone filter is different. It has a spring loaded swing gate in the entrance, at low gas flows the gate is almost closed ,but at high gas flows the gate comes open. This keeps the gases traveling to the out side wall and causes the spinning downward motion then slows down dropping the particles out of the gases and then spins upwards into the exit pipe. This cyclone works at low speeds and high speeds.
There is a deflector that is not shown for the entrance square tubing and connection.
Thats good. My heart sank when I up loaded the pictures with all the detail of my WK firetube there in plan sight. I do not want Chris S. having to talk to me again. Lol.
Bob
bob, thank you very much for the detailled doku of your cyclone, the swing gate i have read about in tilmans swiss book…
the inner pipe of my second cyclone i have made deeper down, approximately 3/4 or one inch down under gas entrance, the first of the red mower is simil like yours…but seems also the longer pipe works well, i think because of the absence of a conus…
ciao giorgio
Stephen Abbadessa said on his website that you want the diameter of the cyclone to be 3 times the inlet pipe diameter. So a 2" would need a 6" cylinder portion.
He uses a straight cylinder and gets decent results.
The main thing I have observed is the cyclone should not be a point where you are causing gases to drag because of restictions. This is why I built the gate type entrance that will open if needed. It closes on low gas demand and opens up on high gas demands, this keeps the gases spinning in the cyclone causing the particals to fall out.
Any extra gas drag in the system can work against you in your gasifier.
A example of this is in my 92 Dodge Dakota WK Gasifier. It should be able to run a much larger engine. But I have a restriction at the intake of the auto mixer. It’s gas opening is only 1 7/8" opening not 2" opening. Only a 1/8" is enough to limit my gasifier operation, if I open my manual add extra gas valve what a difference at highway speeds. It excellerates faster and I can get more speed. I am sure I could over pull my WK Gasifier with the manual valve open.
Now lets move that restriction to the cyclone filter area, it would be the same results of limiting the gas flow to the engine.
I am sure this was why Wayne chooses the drop box instead of the normal fixed opening intake of a cyclone filter when running a WK Gasifier. Less restriction of gases flowing at higher end perfomance.
This all changes when operating a charcoal gasifier, or I should say other gasifier designs.
My rule of thumb. Is this the restriction should be a the hot lobe of the charcoal at the restriction opening if you have one, or above the grate if you have one. Not in your filter area or intake opning of the engine or any where else in the gasifier system ahead of the hot lobe or after the grate area.
These are my thoughts on of what I have observed in my gasifier builds and my operations only.
Yours may differ.
Bob
The gate directs the gases to the outside wall of the cyclone causing the gases to spin down the wall of the cyclone the gases form a vortex movement as it goes to the bottom then the particals drop out as the gases slow down and vortex back up slowly into the exit pipe. When the vortex changes direction the particals fall into the bottom trap or holding area to be dump out later.
Bob
He was aiming for an easy build and was only get about 90% of the stuff. You can get like 99+% with a cyclone But you have to design it for the proper airflow, and they work best with constant velocity which is harder to achieve with a ice engine. Different velocities within the same cyclone will get different results as to how fine of particles it can remove.
For good cyclone operation, there is some math’s behind it, thus I was asking if there was a chart that went with it.
Sean, unfortunately I have to disappoint you, I saved this dimensional document years ago when a now deceased master designed a cyclone in the production process because there was a lot of dust and we had to change filters daily, the cyclone eliminated more than 90% of the dust. Unfortunately I don’t have the full flow data document, but I think if you have a 1 "tube reduce the dimensions from the sketch above 5x and it will work optimally.
No disappointment. I kind of figured that was the case, but was hoping it wasn’t Two posts prior to yours has a reference to a book with the needed calculations in probably a little more detail then needed to try and calculate. I’m sure most people don’t feel like doing all the math either.
I feel like 90% efficiency is more than acceptable given the simplicity of the construction. As long as it stretches out the time between cleaning intervals for my cooling rails and gives the bag filter an easier time I’ll take it. I more or less am just trying to prevent embers from burning the cloth of my filter.
Right, that is the trade off in a nutshell, and an explanation of the saying “the last 10% is 90% of the work.” I was really just curious if Tone had the cross reference chart. I was guessing no, but thought I would ask anyway.
Sean , if you download the file from Eddy Ramos, the information you are looking for is, for example, for a flow of 5.5 l/s, the inlet pipe cross section is 1". As far as I can conclude from this data, the velocity of the gases through the inlet is about 11 m/s. This is a key piece of information for sizing.
first foto the provisoric foam filter mad from a honey can…
second foto, filter housing from aluminium and stainless…
third foto, filter on the engine, note excenter position of rubber hose fixing, this allows mounting in different positions and closure frame with centered pressure…
first try, the coal was a bit humid and some water stands in the main filter and also in the foam filter on the bottom…there was no dust on the throttle…
with really dry coal a little bit of dust goes also through the foam…
the foam is from a visco-elastic bed materass…
the engine was good to start.
the dust on the foto was from some hours working
Two posts prior to yours has a reference to a book with the needed calculations in probably a little more detail then needed to try and calculate. I’m sure most people don’t feel like doing all the math either. 
