Hi,
does anybody have suggestions for how I can shoot a water drop vertically upwards around 6 to 10"?
I have tried a solenoid with the water under pressure but it just makes a mess everywhere.
Well what size nozzle did you use? If your nozzle is too big it isn't going to work. You have to have the pressure be high enough to get the water where you want. Then it is just a matter of getting a pump (or something) that will force the water through the nozzle.
I am not sure how you would get just a drop to shoot out though.
Tried 6mm and 12mm nozzles. 6mm is the smallest I could find.
Not sure solenoids are the way to go but this is all I have at the moment.
Looking for other ideas.
When you say "a" drop, do you mean that literlly?- one solitary drop?
I'm imagining a small hypodermic syringe (probably without needle) filled with water, pointing upwards. It's fitted in some kind of clamp which is attached to a solenoid or a servo or some other actuator. On command, the actuator jerks downward, tapping the thumb thingy on the end of the plunger on the table. The impact of the plunger on the table then shoots the water out the nozzle. Trial and error, and perhaps a bit of physics, will arrive at "just the right" impact to shoot "just the right" amount of water "just the right" height.
You haven't properly described your apparatus. It would be illustrative to know the purpose of this, and how repeatedly and rapidly you need to do it.
A solenoid sounds good, but it will need to be quite powerful, such as the drain valve actuator (not the inlet valve) from a washing machine, powered by mains and controlled by a relay. It needs to operate a diaphragm pump, such as the one in a fishtank pump.
Depending what you're trying to achieve, it may be possible to achieve it by dropping a single droplet down onto a container of the same fluid. High speed video shows that it's common for this to eject a similar droplet back up. It's less obvious than just squirting a droplet upward in the first place, but it seems to me that it might be a lot easier to make something that drips rather than something that squirts iyswim.
Sand_HK, did u have any luck? I just came on here looking for solenoid advice to do pretty much the same thing.
Did u have enough pressure I.e if you ran pump and left valve open the water stream reaches over 10"? Maybe the solenoid valve isn't switching fast enough. If you switch on for say 1s can you get a short stream (long droplet) of water?
Also I think key May be to have a small nozzle.
Drop a marble in a bucket, very difficult just to get just one stable drop though, gravity surface tension wont allow it unless its in freefall and has time to stabilise.
From experience , - photography.
Maybe printing a pump would work. Check out this site Mini Centrifugal Pump by Madox - Thingiverse If you look up 'printed submersible pump' on YouTube, you can see how they work.
look as it were a bullet , you will need some force to give it speed
example use compressed air and a long straight thin pipe (the syringe is very good idea,) now insert one drop of water with your solenoid and enough pressure in your container. the drop will shoot out
this technique is used in las vegas and the aquanura efteling.
with a lot of solenoids i have seen acharacter but this was with falling water.
I think the droplet is likely to become a mist at the speed required to get it 6 to 8 feet in the air.
You could experiment with rising column of air.
Likely would Only work for very small droplets though.
How about using syringe (horizontally) until small drop forms on tip. Then, servo attached to syringe "flicks" the drop into the air?
Why are you trying to do this?
polymorph:
I think the droplet is likely to become a mist at the speed required to get it 6 to 8 feet in the air.
Who mentioned feet?
Yes, this is an issue even so, you get a small jet, not a drop, because there's far
more energy than surface tension can contain.
The way ink-jet print head works is to have a chamber with a diaphragm behind a
nozzle. The diaphragm is pulsed to knock enough fluid out of the
chamber. Refilling the chamber can probably just be done with gravity flow if the
nozzle is small enough so surface tension prevents leakage between drops.
I think nozzle sizes need to be something like 0.5mm or less, not 6mm. Even so that's a lot
larger than ink jet printers, but you want to reach 10" so its all going to have to scale up...
I think there could be a lot of experimentation unless you find an existing system
documented that does something similar already.
Doh! Don't know how I got "feet" out of that.
I would think that the water coming out of the water apparatus (probably a constant diameter smooth bore tube) should be moving at its required velocity prior to exiting the apparatus. Trying to "fire" a water drop probably won't work. Probably various simple low pressure/velocity experiments would be useful.
I think got it.
Think of a thin-ish straight straw, with a hole on a side (a few mm diameter).
Have the straw partially submerged under water, with the hole a few mm below the water line. Something like in the high-end illustration below,
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---------- water line
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| hole here
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/\
Now experiment with bursts of compressed air of different pressures from below. I'm pretty sure you'll get a clean drop launched.