B Question about a vacuum ejector (vacuum pump using the Venturi effect)

[nicolas1409]

TL;DR Summary

What happens to a vacuum ejector if the pressure drops

I have a vacuum ejector and with a suction cup that drops items. think maybe it could be a pressure drop. but what happens if a vacuum ejector gets less pressure, does it suck less? know it's something with bernoulis

 

[nicolas1409]

If the pressure decreases, the total energy must decrease and thereby the principle of conservation of energy can be used

 

[hmmm27]

If you mean "does a suction cup suck less when atmospheric pressure decreases" then yes.

If you're at seal level you have ~14psi pushing against the cup from the outside. At 20,000 feet altitude, less than that : ~7psi.

Technically of course the suction cup isn't sucking, the atmosphere is pushing.

 

[nicolas1409]

A vacuum ejector run on compressed air and I wonder if it falls. and the explanation for that.

 

[Lnewqban]

Welcome, @nicolas1409 !

With less static pressure upstream the nozzle, less fluid leaves it and less is dragged along it.
Yes, less working pressure leads to less useful vacuum.

Please, see:
https://en.m.wikipedia.org/wiki/Vacuum_ejector

 

[nicolas1409]

Thank you very much for the warm welcome

I'm still having trouble finding a spicefict place it says it. After looking several times.

 

[Dullard]

"Yes, less working pressure leads to less useful vacuum."

Not just correct, but precisely correct. Kudos, sir! (color emphasis mine).