Pressure theory applied to a Venturi tube

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SUMMARY

The discussion centers on the pressure dynamics within a Venturi tube, specifically addressing why the pressure at the inlet and outlet is greater than at the throat. This phenomenon is explained through Bernoulli's equation, which illustrates the conservation of energy density. As the fluid flows into the narrower section of the tube, its velocity increases, resulting in a decrease in pressure due to the conversion of pressure energy into kinetic energy.

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  • Understanding of Bernoulli's equation
  • Basic principles of fluid dynamics
  • Knowledge of energy conservation in physical systems
  • Familiarity with kinetic energy concepts
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  • Study Bernoulli's equation in detail
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Students and professionals in physics, engineering, and fluid dynamics who seek to understand the principles governing fluid behavior in Venturi tubes and similar systems.

extricate
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Hi,

I'm a little confused about the pressure in the inlet/outlet and the throat of a Venturi tube.

Why is the pressure in the inlet/outlet greater than in the throat? I thought that because air is needed to flow into a smaller space so the pressure has to be greater?

Pardon me. I've self-learning.

Thanks for your time.
 
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welcome to pf!

hi extricate! welcome to pf! :smile:

it's conservation of energy (density) …

Bernoulli's equation is simply a conservation of energy (density) equation

(and pressure is energy density: pressure = work done per displaced volume = energy per displaced volume)

where the tube is narrower, the speed is faster, so the kinetic energy density is greater

so the pressure must be less :wink:
 
Thanks a lot for the reply.
 

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