Flow Problem (inventive thinking exercise)

bvy · Jul 25, 2017

Seems no one makes a funnel with two outlets. I'm wanting to build an application that allows me to pour liquid into a funnel (or the like) and divide or divert the liquid roughly equally into two separate chambers. I've entertained some ideas but they all have all have drawbacks such that one chamber gets sufficiently more liquid than the other. Thoughts?

dpurdy · Jul 25, 2017

How large? There are splitters that fit on faucets with two hose connections. You could find a way to attach a funnel to the top of it and a small length of hose to the two outlets..

~andi · Jul 25, 2017

http://www.gardena.com/de/produkte/bewasserung/ogs/2-wege-ventil-33-3-mm-g-1/900877401/

bvy · Jul 25, 2017

dpurdy said:
How large? There are splitters that fit on faucets with two hose connections. You could find a way to attach a funnel to the top of it and a small length of hose to the two outlets..

Not large. Maybe a liter of liquid. The hose fittings might be overkill. But I'll take a look.

John Koehrer · Jul 25, 2017

Howz about Edmund Scientific or Science and Surplus?
My feeble memory seem to have a glimmer of some mad scientist glassware

grahamp · Jul 26, 2017

Flexible tubing and a 'Y' connector on the end of the funnel. One thing you will have to watch for is keeping the section from the funnel to the Y vertical. Otherwise the flow will be biased in one direction.

bvy · Jul 26, 2017

grahamp said:
Flexible tubing and a 'Y' connector on the end of the funnel. One thing you will have to watch for is keeping the section from the funnel to the Y vertical. Otherwise the flow will be biased in one direction.

This has been my thought all along, but finding a Y-connector is proving difficult! 1/2" or 3/4" seems ideal.

dourbalistar · Jul 26, 2017

bvy said:
Seems no one makes a funnel with two outlets. I'm wanting to build an application that allows me to pour liquid into a funnel (or the like) and divide or divert the liquid roughly equally into two separate chambers. I've entertained some ideas but they all have all have drawbacks such that one chamber gets sufficiently more liquid than the other. Thoughts?

The human body acts as a funnel with two outlets as you describe, but with the same problem such that one chamber gets sufficiently more liquid than the other.

Kawaiithulhu · Jul 26, 2017

All depends on how accurately divided the volumes need to be.
10% difference? Probably pretty easy.
1% difference? Probably getting into chaos theory and God playing dice every time you pour

bvy · Jul 26, 2017

Kawaiithulhu said:
All depends on how accurately divided the volumes need to be.
10% difference? Probably pretty easy.
1% difference? Probably getting into chaos theory and God playing dice every time you pour

Yeah, I remember those models. Nonlinear dynamics. +/-5% is ideal.

pdeeh · Jul 26, 2017

bvy said:
This has been my thought all along, but finding a Y-connector is proving difficult! 1/2" or 3/4" seems ideal.

I just plugged "y connector" into ebay and got 13,580 hits

Kawaiithulhu · Jul 26, 2017

This idea will make your apparatus larger but less prone to chaos:

1) Make the receiving end of the funnel capable of holding much more volume so you're not pouring directly down the outlet
2) Go with a smaller diameter Y connector chosen from those 13,580 sources to back up the liquid you're pouring in
3) The back pressure and constrained flow will kill turbulence that would normally make the splitting unreliable

But then that kind of breaks the idea of having a funnel to quickly pour stuff through...

bvy · Jul 27, 2017

pdeeh said:
I just plugged "y connector" into ebay and got 13,580 hits

Been there. Mostly garden hose connectors and audio cords. I neglected to add that I started this project with PVC pipe, so I was looking for something that wasn't a T connector or "wye" connector (straight piece with an angled offshoot). If I use flexible hose I see something that might work, but then I have to worry about the hose kinking or collapsing and constraining flow that way.

Kawaiithulhu said:
But then that kind of breaks the idea of having a funnel to quickly pour stuff through...

I think it's still doable. And your ideas confirm what I had in mind -- that the pipes/hoses should be full to capacity and the funnel should "back up" with liquid so that the liquid is channeled equally down the two paths (using a Y connector).

mshchem · Jul 27, 2017

I've used devices made for powders . We called them "rifflers" . How bout taking some 2 inch PVC pipe and putting small hose barbs on a cap on the end ? I would think both hoses would drain at the same rate ? If you want a funnel shape get a 4 in to 2 in adapter . Maybe clamp to a ring stand . Sounds like a neat idea .
Maybe mix 5 L of XTOL , rig up 5 hoses and fill 5 1 L bottles ☺

esearing · Aug 22, 2017

simple.
Create a T_shaped tubing from your funnel. At the end of the T shapes you need a stopper for your bottles with a hole or tap for the tubing to connect. Turn the bottles upside down and place your funnel higher. gravity will equalize the volume, but you will have to figure out how to get the volume remaining in the tube. You could maybe turn bottles on their side instead of upright. small shut off valves may be needed too near the stoppers.

Funnel
bottle | bottle
stopper ---- | ---- stopper

paul ron · Aug 23, 2017

^ this sounds like the best solution. liquids will find their own level on both sides of the y. its the old carpenters liquid level method.... at least I think that's what he's getting at.

but you will have to figure out how to vent your bottles so you get a uniform flow and not create a vacumn or pressure.

Flow Problem (inventive thinking exercise)

Privacy & Transparency

Privacy & Transparency