Smiles...
I was reading thru that one yesterday, or the day before. At least I am beginning to learn how to find the pertinent info. Perf. trays are easier to build, and from what I've read are much more efficient but they HAVE to be designed correctly for the column or they are useless.
Bubble caps are more forgiving to run by nature but require more energy to gain the same result as Perf. trays due to less interaction area. I'll spend the night reading more, and try to make a decision.
More numbers for posterity using a 4" inner column
Area of 4" inner with a 3/4" vapor injector 3.8"
8" 4" Inner column 7"
Vapor speed for 3.8"@ 7.5 kw 76cm per second
7" @ 7.5kw 23cm
Column overall volume 27.5 liter equivalent to 11.1' x 4" column 18 plates
Much closer. I do recall your mentioning vapor speed differences at the very beginning of this idea YummyRum. It took me a few days to catch up, and understand exactly what impact they would have on designing.
Thank you! Thank you! thank you!