Inline Thumper Downcomer Cap Size

[WTDist]

Im re-looking at inline thumper threads and im wondering how big the downcomer caps need to be :think:
I get the high bubble cap, high riser and downcomer below the riser but im wondering how big of a cap needs to be on the bottom of a downcomer :think:

im throwing ideas around my head at the moment of a 4" or 6" with a depth of 130mm and im wondering how i would go about the downcomer cap.

should it be as big as the bath depth itself to avoid the vapor pushing up the downcomer instead of the riser or can it be smaller or shaped different?

Just trying to draw up some ideas in my head and get an idea where i want to go with my equipment before i start/finish :handgestures-thumbupleft:
my idea is because im making some plates for my 2" T500 boiler and im thinking if i do 3 caps at 20mm and one 6" at 130mm i can get all the wash in the column and not the boiler and go from there. Im not after speed and my funds are low. i just want a good separation single run for my 25L boiler.

already started on the 2" plates so im thinking maybe i should do a thumper instead of a 4th plate. Just ideas for now and depends on how i need to make it and finance

Cheers
WTD

[Meatheadinc]

should it be as big as the bath depth itself to avoid the vapor pushing up the downcomer instead of the riser

:handgestures-thumbupleft:

a j-trap extending back up the riser occupies less vertical space :shhh:

[WTDist]

ahh thx meat thats some clever thinking :handgestures-thumbupleft:

am i right in assuming the j trap should be just as high up the riser as the height of the downcomer (level like a U shape)? or is + or - a few mm acceptable considering it will be below the riser top?

[drinka]

ahh thx meat thats some clever thinking :handgestures-thumbupleft:

am i right in assuming the j trap should be just as high up the riser as the height of the downcomer (level like a U shape)? or is + or - a few mm acceptable considering it will be below the riser top?

I'm curious to know this as well. Any chance of a pic of your j-trap downcomer meat?

[maddogpearse]

If you made it as high as the riser, liquid couldn't flow back to the boiler.

[WTDist]

heres a very basic paint drawing i did in 2 mins. shows j trap level with riser. looks like it will work but i would add 5mm just to make sure, like the green part in the pic. The cap is not in the drawing

Untitled.png

[Meatheadinc]

Give it some more fall under the plate.
More of a J shape instead of a U. Then the
output is lower than the downcomer to allow easy draining.

[drinka]

Thanks fellas :handgestures-thumbupleft: