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karimwassef
07/13/2017, 03:44 PM
I'm working on improving my surge design and one issue is vortex-generated bubbles. I can eliminate it by using a downward facing elbow but that also critically cuts down flow.

So- I'm thinking of a surface control mechanism using ping pong balls on a mesh so that the surface stays flat - no whirlpool.

Anyone done this or thought of something like this?

I've looked into vortex breakers but they all reduce flow by adding friction or pressure barriers (baffle plates, radial ribs)... all things I don't want. Also, they could stop an open large vortex but still create several small vortices

https://en.m.wikipedia.org/wiki/Vortex_breaker
http://www.piping-designer.com/images/disciplines/mechanical/process/stationary_equipment/vessel/Vortex_Breaker_2.jpg

http://lh4.ggpht.com/webwormcpt.wwcpt/SIYUlvEHL3I/AAAAAAAABwc/fPvjgHJxSRA/s800/Vortex_breaker_sketch.PNG

So I'm back to my idea with ping pong balls tied together into a mesh. The idea is to disrupt the airflow above the water without compromising any of the water flow.

karimwassef
07/13/2017, 03:52 PM
Maybe a wood plate sitting on a foam plate?

ericarenee
07/13/2017, 07:56 PM
Totally Different way with no testing.. But but but


what if your surge tank Was a series of Pvc pipe snaked above the Display tank. say 2 inch pvc with a 3 inch output to the tank. This could give you a longer more controlled surge with no Bubbles.. .. Its just a thought and have not tested it at all..

karimwassef
07/13/2017, 08:14 PM
The current surge drum design is a 36" diameter that's 80" high. There are 10 x 3" PVC pipes that connect to the side front.

I see your point that many small pipes could be made into a surge but each pipe would create friction resistance slowing down the surge flow compared to the 36" walls. How much resistance? I'd need to calculate.

The fact that there are 10 x 3" PVC outlets could already curb the creation of one massive vortex but I'm expecting 10 small thin vortices instead :)

karimwassef
07/13/2017, 08:25 PM
<a href="http://s1062.photobucket.com/user/karimwassef/media/Designs/2_zpsjcpwgwyh.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/Designs/2_zpsjcpwgwyh.jpg" border="0" alt=" photo 2_zpsjcpwgwyh.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/Designs/0_zpsu4zd3sy1.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/Designs/0_zpsu4zd3sy1.jpg" border="0" alt=" photo 0_zpsu4zd3sy1.jpg"/></a>

<a href="http://s1062.photobucket.com/user/karimwassef/media/Designs/1_zpsm69vllvq.jpg.html" target="_blank"><img src="http://i1062.photobucket.com/albums/t496/karimwassef/Designs/1_zpsm69vllvq.jpg" border="0" alt=" photo 1_zpsm69vllvq.jpg"/></a>

figured I'd show the whole setup

ericarenee
07/13/2017, 08:59 PM
Again NO DATA Just a thought..
Where you have 10 pipes draining one BIG TANK. What if each of the 10 had equal amount of water behind them in a Series of pipes Actually some type of flexible pipe would be best snaked upward at angles . that should create quite a Surge. The down side prob less vicious but defiantly a longer surge


Again guessing..

karimwassef
07/13/2017, 09:08 PM
It would work but instead of a 350 gallon surge, I'd only get 10 pipes worth of water. At 3", that 25 gal. If I used 12" PVC, that would be ~ 400 gallons.

That's an interesting concept at the 12" PVC level but I'd need to connect them all at the top to draw the water in from all of them. I'd also need to make room for that many pipes somewhere.

Still, the flow would slow down by virtue of more walls to run up against. A 12" pipe would also potentially experience a vortex as it empties... just smaller. Now I need lots of ping pong mesh covers. :D

Very interesting though - worth thinking about.

karimwassef
07/13/2017, 09:13 PM
Ran the numbers and it would just cost too much at 12" diameter. It's $16/ft and I'd need over 60ft ~ $1000... ouch

The 36" PE drum is 325gal at $350

https://www.ntotank.com/325gallon-acerotomold-white-opentop-containment-tank-x8666939

I'd need to go down to 8" which is ~ 175 gallons (half the volume) to get the PVC at ~ $7/ft to end up at ~$420

Too $$$

jccaclimber
07/13/2017, 09:13 PM
I would clamp the ping pong balls in egg crate, I still like your PE float idea as well.

I wonder what the largest reasonably priced DWV pipe is? Takes more space, has more loss, but that might not be all that unreasonable. Connection at the top is either a large manifold or a series of connecting tubes, that isn't terrible. I think the uniseal octopus out of a big tank will turn out better, but the tube/tanks are probably worthy of some minor research. That's how a lot of large factories do air "tanks". At some point there's just enough line that you don't need a tank.
There are actually some accumulator tanks in the air system where I work, but that's mainly because the air system isn't really big enough to properly move air from the 700 hp of air compressors we have.

karimwassef
07/13/2017, 09:24 PM
Wonder if just putting an eggcrate grill flat in the drum above the output, then just dunking in 50 ping pong balls wouldn't work. Might create too much weight though.

jccaclimber
07/13/2017, 09:30 PM
You don't want the egg crate anywhere other than the surface, remember the losses of passing through mesh.

karimwassef
07/13/2017, 09:31 PM
To match the tank price, the pipe needs to be $5.25 a foot and be 11" in diameter

jccaclimber
07/13/2017, 09:41 PM
Using Lowe's as a starting point (I'm sure you can do cheaper elsewhere, but maybe not), 6" dwv is $2.89/ft in 10' lengths. Moving up 8" dwv is $6.90/ft +tax in 20 ft lengths. It goes up pretty fast when you go to 10" and 16" pipe. All of these list as schedule 40/dwv, so I'm not sure if this is solid wall sch. 40 that can be used as dwv, or the foam wall sort of dwv.
More importantly the fittings will really kill your wallet.

It would take a horrific amount of space and look awful, but I have an image in my head where each 3" surge pipe has its own IBC tote behind it. You could do a long duration flow with a couple flip switches where the totes flow down though the tank, then to a sump while the other set is refilling from the sump. Seems like an awful lot of complication to avoid impellers, but just another idea.

karimwassef
07/13/2017, 09:46 PM
That's slow flow.

I'm using double tank balance to avoid going to the sump altogether. And the height sets the flow rate so IBC totes don't give me the volume at height.

Seems like anything over 4" pipe is super expensive and couplings go up over 3".

I want to stick with manipulating the air above the water surface or controlling the interface to avoid the vortex. Air resistance doesn't slow me down.

karimwassef
07/13/2017, 09:54 PM
They use black plastic balls to control evaporation in reservoirs (& stop algae)
http://duwaterlawreview.com/wp-content/uploads/2015/10/20150813_101113_shadeballs.jpg

http://www.batinvestments.com/f-users/user_106458/website_107403/images/thumbs/W_960_6fdac9_4d4732f4ea68474d9c18fc201bdaa7b7.jpg

http://www.latinamericanscience.org/images/shadeballs.jpg

http://www.dailymail.co.uk/news/article-3204873/How-100-million-shade-balls-brought-protect-LA-s-reservoir-evaporating-fact-bacterial-nightmare.html

http://www.plasticballs.com/plastic-balls-polypropylene.html

jccaclimber
07/13/2017, 09:59 PM
There is a hotel somewhere near Valparaiso, IN that has a pool that is half indoors, half outdoors. They put plastic play pen balls on the outdoor half during the winter and it keeps it surprisingly warm on that half. It's very nice, cold air for your head (it was snowing once while I was there), but everything below the surface is very warm. I'm sure it also cuts down significantly on their evaporation.

Different problem though, you need some local resistance at the surface, which is not the same thing.

karimwassef
07/13/2017, 10:21 PM
$200 per cubic meter (1000 balls)

https://m.alibaba.com/product/60697345697/4-Inch-100mm-PP-Polypropylene-HDPE.html?s=p&spm=a2706.7843667.1998817009.19.6z7P5z

But what to do with the 900 extra balls???

karimwassef
07/13/2017, 10:22 PM
Wouldn't the balls create rotational resistance and stop the vortex?

karimwassef
07/13/2017, 10:25 PM
I found cheaper ones... $50 per 1000 but they're foam and not appropriate for RC

jccaclimber
07/13/2017, 10:37 PM
Some resistance as they bounce off each other, but they will contour to the surface in a way that a plate will refuse to do.