Increase Velocity of Fluid: Less Pressure?

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SUMMARY

The discussion centers on the relationship between fluid velocity and pressure, specifically referencing the Bernoulli equation and the continuity equation. It is established that as fluid velocity increases, pressure decreases due to the conservation of mass and energy principles. The continuity equation ensures that the volume flow rate remains constant, leading to higher speeds in narrower sections of flow, which in turn results in lower pressure. This phenomenon is a fundamental concept in fluid dynamics.

PREREQUISITES
  • Understanding of the Bernoulli equation
  • Familiarity with the continuity equation in fluid dynamics
  • Basic principles of conservation of mass and energy
  • Knowledge of fluid flow behavior in varying cross-sections
NEXT STEPS
  • Study the derivation and applications of the Bernoulli equation
  • Explore real-world examples of fluid flow in pipes with varying diameters
  • Investigate the implications of fluid dynamics in engineering applications
  • Learn about the effects of viscosity on fluid flow and pressure
USEFUL FOR

Students and professionals in physics, engineering, and fluid mechanics, particularly those interested in understanding the dynamics of fluid flow and pressure relationships.

bluejay27
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Why is there less pressure if the velocity of the fluid is increased?
 
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I obtained the answer! It deals with the continuity equation, where the mass of a moving fluid does not change as it flows. Thus, the volume flow rate has to be equal at all times.
 
Nevermind that still does not answer my question. Why is there less pressure when the velocity of fluid is increased?
 
bluejay27 said:
Nevermind that still does not answer my question. Why is there less pressure when the velocity of fluid is increased?
You can look at the Bernoulli equation! Since, the left side of its equation is constant, the right side must equal to each other. If there is a smaller cross-section, there will be a higher speed and in order to make the equation equivalent to the left side of the equation, the P at the right side of the equation must decrease.
 
bluejay27 said:
I obtained the answer! It deals with the continuity equation, where the mass of a moving fluid does not change as it flows. Thus, the volume flow rate has to be equal at all times.
That's one of two parts: that's conservation of mass (flow). The other is conservation of energy.
 
ive often wondered what causes the molecules to accelerate. some say that the neck down is a kind of "velocity filter" and allows the high speed vibrations of the molecules to prioritize the ones pointed in the right direction, through.
 
Been a while since I took physics, but I believe that because the left side of the Bernoulli equation stays constant the pressure must vary proportionally with the velocity. So as the water speeds up, it must exert a lower pressure on its surroundings.
 

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