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Re: Chocko's Bubbler begins...!
Posted:
Sat Jan 05, 2019 8:41 pmby db1979
RC Al wrote:Ive seen slots like that at the top of a downcomer - in theory to break the surface tension of the bubbles so they collapse better before entering, without the bubbles we could use a much smaller tube - running bubble free water through it isnt a good test
While looking for a flow rate chart, I may have solved the length riddle too - there's a minimum length for a pipe to overcome the viscosity of the fluid vs the drag on the walls, check out the attached chart, the thing that would affect those numbers is the difference in viscosity of alc to water - alc is aprox 20% thicker so there would be a change in those numbers (by a different amount, beyond my paygrade) so all the way down to the next plate could make it more efficient.
This applies to tubes that are full of liquid. A downcomer has liquid running down it's sides and then pools in the cup below, before overflowing to the next plate. The maximum amount that can go down a downcomer is given by the RC, as condensed vapour drops down and fills the top plate, then overflows into the downcomer and then to the plate below and so on. The heat input and length of RC required to provide the condensate to keep a 3/4" downcomer completely filled would be excessive.
I don't think there's any reason to have long downcomers.
Re: Chocko's Bubbler begins...!
Posted:
Sat Jan 05, 2019 8:41 pmby db1979
Great work chocko, keep it up :handgestures-thumbupleft:
Re: Chocko's Bubbler begins...!
Posted:
Sat Jan 05, 2019 9:06 pmby RC Al
If it's " only running down the sides" a smaller down comer could be used?
would it be unreasonable to say that the bubbles add enough volume to make it act like a full pipe?
1/2" ain't enough for a 2-3000w 4" - it's not refluxing 150 gallons per hour - the pipe is full
Re: Chocko's Bubbler begins...!
Posted:
Sat Jan 05, 2019 9:15 pmby hillzabilly
Just looking at my very well used FSD downcomers and the internal size is less than 1/2inch and I have pushed 5000wt thru them and they performed faultlessly as usual.cheers hillzabilly ;-)
Re: Chocko's Bubbler begins...!
Posted:
Sat Jan 05, 2019 9:56 pmby RC Al
First up, sorry for the thread derail chocko... :roll:
This is what happens with assumptions, a very high percentage of the posts on plates/down comers say to go 19mm to avoid flooding..... haven't seen an argument against it...
Re: Chocko's Bubbler begins...!
Posted:
Sat Jan 05, 2019 11:12 pmby hillzabilly
Sometimes the discussion may go a little away ,but as long as its productive for the build and others like your own now you have bought a started build ,and are trying ta sort out specs then its all about why we are here.cheers hillzabilly ;-)
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 06, 2019 5:50 amby Chocko6969
RC Al wrote:First up, sorry for the thread derail chocko... :roll:
This is what happens with assumptions, a very high percentage of the posts on plates/down comers say to go 19mm to avoid flooding..... haven't seen an argument against it...
No problems, it's all information and I'm not complaining! :-D
:text-+1: to hillz above
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 06, 2019 8:09 amby scythe
The thing with 5star downcomers is that they are not 1/2" at the top.
You need a large opening to assist with "popping" the bubble so the liquid can go down.
If you only had a 1/2" opening at the top of the downcomer then it would be prone to getting "flooded" with un-poped bubbles.
By using 3/4" tube it an easy solution.
You could use a 3/4" - 1/2" reducer at the top of a 1/2" downcomer if you really wanted to use 1/2" downcomers but as 3/4" is less soldering why not.
If using the reducer idea, just keep an eye on liquid bath depth.
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 06, 2019 2:21 pmby hillzabilly
I did post a pic of the plates I use with a piece of 3/4 tube added to the dowmcomer and a couple of holes for drainage added ,they have worked very well for me,SJC's build has the details,as this also gave me the ability to change the standard bath depth of the FSD downcomers to 25mm for the large 2inch single caps I got from them.cheers hillzabilly ;-)
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 1:53 pmby Chocko6969
OK, it seems I too couldn't help myself, had to clamp it all together and have to say I'm pleased with it! If it works I'll be even happier too!
It's a tad wonky but that's my fault and not the boily who welded the ferrule, I stuffed it up but a small chock will sort it out.
Just waiting for the cooling system gear and I'll be into the vinegar run, wife and kids away for a few days soon so best get it sorted!
Chocko
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 2:06 pmby Georgio
Chocko its a thing of beauty! Nice work :handgestures-thumbupleft:
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 2:22 pmby bluc
Looks awesome :handgestures-thumbupleft:
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 3:46 pmby hillzabilly
Interesting parrot mate ,a 1/4inch valve on it would be smaller and more than enough for draining duties,good luck with the maiden voyage hope she goes as good as she looks.cheers hillzabilly :handgestures-thumbupleft:
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 4:00 pmby RC Al
Looking like the biz mate, good luck on the run :handgestures-thumbupleft:
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 4:05 pmby Chocko6969
hillzabilly wrote:Interesting parrot mate ,a 1/4inch valve on it would be smaller and more than enough for draining duties,good luck with the maiden voyage hope she goes as good as she looks.cheers hillzabilly :handgestures-thumbupleft:
Thanks fellas! Yes hillz I'll be changing that later coz I want to get rid of that brass. I've actually tinned the inside so there's no leaching but you're right, I'd prefer something smaller and not brass if I can find it.
Chocko
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 4:07 pmby Professor Green
Superb build Chocko, top notch work.
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 4:14 pmby Chocko6969
Professor Green wrote:Superb build Chocko, top notch work.
Thanks mate, just don't zoom in too close! :D Not a lot of sanding/polishing gone on here but it's what I'm happy with!
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 4:26 pmby dans.brew
Nice looking rig mate!!
Have fun running it on its maiden voyage. :dance:
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 4:34 pmby hillzabilly
Chocko6969 wrote:hillzabilly wrote:Interesting parrot mate ,a 1/4inch valve on it would be smaller and more than enough for draining duties,good luck with the maiden voyage hope she goes as good as she looks.cheers hillzabilly :handgestures-thumbupleft:
Thanks fellas! Yes hillz I'll be changing that later coz I want to get rid of that brass. I've actually tinned the inside so there's no leaching but you're right, I'd prefer something smaller and not brass if I can find it.
Chocko
Most put the valve on the end of the actual parrot tube ,so as to get a more complete drain and not to offend the smearing gods.Have tinned the inside of one or two brass fittings myself,its a shame brass solders so nice too.cheers hillzabilly ;-)
Re: Chocko's Bubbler begins...!
Posted:
Sun Jan 13, 2019 5:41 pmby Chocko6969
hillzabilly wrote:Chocko6969 wrote:hillzabilly wrote:Interesting parrot mate ,a 1/4inch valve on it would be smaller and more than enough for draining duties,good luck with the maiden voyage hope she goes as good as she looks.cheers hillzabilly :handgestures-thumbupleft:
Thanks fellas! Yes hillz I'll be changing that later coz I want to get rid of that brass. I've actually tinned the inside so there's no leaching but you're right, I'd prefer something smaller and not brass if I can find it.
Chocko
Most put the valve on the end of the actual parrot tube ,so as to get a more complete drain and not to offend the smearing gods.Have tinned the inside of one or two brass fittings myself,its a shame brass solders so nice too.cheers hillzabilly ;-)
Yes, you're picking everything I am at the moment too.! I'll be doing a retrofit or a complete new parrot after the sacrificial run I reckon, cheers!
Chocko