Air Flow Through Dual Spouts on Laid Down Jug

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SUMMARY

The discussion centers on the dynamics of air flow through dual spouts on a laid-down five-gallon jug. When the jug is positioned horizontally with a 1/2 inch spout, air enters through the spout to replace the exiting water. Introducing a second 1/2 inch spout on top of the jug alters this dynamic, as air is likely to enter primarily through the upper spout due to pressure equalization. The conversation also explores the effects of water pressure and flow rates, particularly when considering the introduction of a reservoir above the second spout.

PREREQUISITES
  • Understanding of fluid dynamics principles
  • Basic knowledge of pressure differentials
  • Familiarity with the concept of flow rates
  • Experience with practical experiments involving liquids and air flow
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  • Research fluid dynamics, focusing on Bernoulli's principle
  • Explore the effects of pressure differentials in fluid systems
  • Learn about flow rate calculations in open and closed systems
  • Conduct experiments with dual spout systems to observe air and water interactions
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This discussion is beneficial for physics enthusiasts, fluid dynamics students, and anyone interested in practical applications of air and water flow principles.

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If you have a five gallon jug of water with a 1/2 inch spout, and it is laid on its side, because there is no other opening in the jug it empties as air spills into the spout and replaces the water, but if the jug would have another 1/2 inch spout on it, now on top of the laid down jug,
Would any of the air still enter through the first spout or would 100% of it now come from the other spout, although probably a simple answer, I'm unsure because I've never took a physics class, but I would assume that 100% would now come from the other opening.
 
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The air outside the jug would be pressing on both spouts,
about the same pressure. But the water would (when deep)
would be going so fast out the exit hole (over 1 m/s)
that "essentially none" of the air would diffuse upstream,
until the jug was almost empty.

try it, with food coloring in the exit stream -
especially right next to the wall of the spout. Air isn't much faster.
 
what if this changed?

If the secondary spout on top had a resevoir of water pressing down on it, would the sucking in of this water hold back the air from going into the first spout?
 
If there's a hole in the top, the pressure at the bottom of the jug (at the first spout) no longer decreases rapidly as the water leaves (since there's never a vacuum made at the top). So the water just flows smoothly out, provided the hole in the top is big enough. (Eventually, if it's air coming in the top, the speed of water flow out the spout will slow, since the water depth decreases.)
 
thanx to lightgrav

I originally posted in as 2112 because I couldn't access my account, thanks for the solutions.
 

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