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Why does a spray bottle work?

alexanderellis.github.io

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Re: Why does a spray bottle work?

#31

Post by Sharlin »

mbell wrote: post #26
TheSoftwareGuy wrote: post #20

One way valves are basically diodes, but for fluids rather than electrons. You can also make logic gates out of just diodes (or one way valves). Imagine writing software for a hydraulic computer!

> One way valves are basically diodes, but for fluids rather than electrons. The analog of the fluid in that analogy is electric charge/current, not electrons which move in the other direction (which kinda breaks the analogy as a result).

And also move really really slowly compared to the field. Their (net) movement is actually pretty irrelevant to the propagation of what we call electricity an sich.

Re: Why does a spray bottle work?

#32

Post by alanbernstein »

maym86 wrote: post #25
userbinator wrote: post #16

A very simple design, based on a principle that was discovered over 2000 years ago. http://www.mdpi.com/2073-4441/7/9/5031/pdf (see page 13-14) https://en.wikipedia.org/wiki/Piston_pump

That diagram at the top of the Wikipedia article made the concept more clear to me than the whole orginal post. Drawing the valves like that really helps. Edit: grammar

That's funny, I don't know what that diagram is trying to convey.

Re: Why does a spray bottle work?

#33

Post by rossdavidh »

mbell wrote: post #26
TheSoftwareGuy wrote: post #20

One way valves are basically diodes, but for fluids rather than electrons. You can also make logic gates out of just diodes (or one way valves). Imagine writing software for a hydraulic computer!

> One way valves are basically diodes, but for fluids rather than electrons. The analog of the fluid in that analogy is electric charge/current, not electrons which move in the other direction (which kinda breaks the analogy as a result).

However, I think it would have been quite difficult for me to get the concept of "holes" in semiconductor current, which are positively charged pseudo-particles created by the absence of electrons, if I hadn't been able to think of them as being like bubbles in a fluid. They go the opposite way of the fluid flow, and they are somewhat particle-like. So it's not a totally broken analogy, it does help to clarify some things.

Re: Why does a spray bottle work?

#34

Post by Sharlin »

jarfil wrote: post #29
billsix wrote: post #13

Having source be in the "staging area" after "git add" makes more sense to me now :-)

I think this use of "staging area" comes from the military use, which in turn comes from the theater "staging", both predating git and the bottle.

Yep, it’s more likely the author got the ”staging area” from git, as an analogy familiar to software engineers (or else from the military/theater context), it’s not an official fluid dynamics term used by spray bottle engineers. At least I don’t think so :p

Re: Why does a spray bottle work?

#35

Post by digi_owl »

jetrink wrote: post #27
TheSoftwareGuy wrote: post #20

One way valves are basically diodes, but for fluids rather than electrons. You can also make logic gates out of just diodes (or one way valves). Imagine writing software for a hydraulic computer!

MONIAC [1] was an analog computer designed in 1949 that used water to model the national economy of the United Kingdom. 1. https://en.wikipedia.org/wiki/MONIAC

Made by an engineer turned economist from New Zealand no less.

Sadly he is better know for a diagram he drew of an observation, the Phillips curve.

I fear that much like this hydraulic model, Steve Keen's work is likely to be ignored or ridiculed by future economists while they fret over religious X diagrams.

Re: Why does a spray bottle work?

#39

Post by fouc »

vanilla-almond wrote: post #28

A few years ago, a British inventor appeared on a TV show called Dragon's Den (UK version of Shark Tank) and pitched his idea of an improved spray bottle called the Anyway Spray. Instead of a normal plastic tube inside a bottle with an opening at the end, he designed a tube with millions of tiny perforations along its length. This meant the spray bottle could operate at any angle (even upside down) and could empty al…

Seems like he managed to license it to Tesco's range of label products. Good for him.

Re: Why does a spray bottle work?

#40

Post by ninkendo »

ninkendo wrote: post #6
amelius wrote: post #4

Wouldn't this design create a vacuum in the reservoir? Edit: (reservoir = bottle)

No, because the one-way valve on the bottle end is pointed the other direction, so that it allows fluid into the reservoir, but not back into the bottle.

(Too late to edit: you’re using the terms correctly, I was wrong. I was thinking of what the article calls the “staging area”)
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