This whole conversation is super cool…I’ve heard of the venturi effect before, but never looked into it.
What types of degrees do you guys have?..lol
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Haha well I’m a systems engineer so I basically mess about with experimental stuff for a living. I have a mate who is setting up a 8 pot dwc, so I am going to attempt to build one of these vortex venturi’s that hopefully works in a real world setting,
note… it’s not MY setup I am game to experiment on this with 
I’ll post some pics of it when I do.
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Just stare at a bong! 
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I wanna experiment with this in a RDWC setup.
I’m worried about burning the pump out with so much restriction on the discharge.
I plan on using a 1000GPH that takes water from control bucket and dumps the water into the totes from a waterfall. This is where I was thinking of install a Venturi. So water would go from the control to a manifold which has branch run-outs to each plant site tote. On the branch run outs would be a Venturi to an elbow down through the tote lid and waterfalling on the water surface.
Water returns to the control via 1" barbed bulkheads and 1" poly.
The branches are 1/2" so not sure how much more I can reduce that for a Venturi effect.
This is the easiest way I see it working with my existing setup.
I first thought of using the barbed bulkheads as the discharge and doing away with the waterfalls and drilling holes mid way on the totes and returning to control bucket via that.
You dont really need a restriction in the water line to have the venturi work as far as sucking air. The restriction is there to force the water to flow faster, which will create more suction than withoout a restriction, but you can get suction just fine with no restriction to the water flow.
Just stick the air line in at a slight angle towards the direction the water is flowing. It also helps quite a bit if you can position the venturi up as hi as possible so there is no static pressure from the water colume that has to be over come.
If you have the venturi on the floor for example, then when you fill the buckets, there will be several inches of water above the level where the air needs to enter the system. That creates pressure and forces the water up into the sir line until its at the same height as the water in the bucket. Then when the venturi starts to work, it has to over come that pressure before any air can start to enter the system.
Instead, position the venturi as hi as possible relative to the ‘full’ or maximum water height in the buckets. That will let the venturi work at max efficiency.
Or here is another option that works just fine - cut the air line end at a steep angle and position it as in the drawing.
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Also, if your pump is magnetic drive, I wouldnt worry about the blockage much. For other pumps, as long as you dont slow them down tooooo much they should be fine…
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Please keep in mind the roots are going to grow thick and long. Last 20 days of 12/12 can be a nitemare…Expect and plan for some sort of system shut down.
Think what the system will do when roots clog drains. Next what going to happen when the power goes out.
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Check this out for an aeration system… uses a venturi to suck air into the main line, and then uses a venturi in in the nozzles to drag water into the stream and mix it with the air… I am thinking I could 3d print one of these nozzles 
From here.
The other thing to consider is an inline ‘static mixer’ like this:
with a venturi like this:
So Pump>Venturi>Mixer if you are using a standard pump or Venturi>Pump>Mixer if you are using a needle wheel pump. TBH, I think with a decent flow, just the venturi and static mixer would provide enough aeration for our needs.
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The bottom picture valve works great…
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A non-optimal but super simple venturi to get started:
Although, the amount of air injected and the bubble size will be dependent on the velocity of the fluid moving past the venturi. The velocity has to be sufficient to pull a vacuum on the venturi.
Here’s an animated gif after passing the fluid + bubbles through a pump with a needle-wheel impeller using the above noted venturi:
FWIW, I like the concept of using a venturi.
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Not sure how a vortex drain at the bottom adds any more air to the system though it does help create a swirling mixing effect which that German guy from the 1800s would claim is a very good thing. The venturi certainly will thoroughly mix air into the water at what ever rate the orifice size will allow. Yes venturis are a very efficient way to add much smaller air bubbles than airstones, Now a vortex at the surface of a Rez tank would help draw in air, but splashing, waterfall, nozzles will also aerate the solution. You are correct that a DO meter would be necessary to measure how much air and how much air at depth
Bruh, I’m in love with your layout and general idea. This is pure genius. Keep us posted.
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