Why Does Differential Pressure Vary As The Square Of The Flow?

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Discussion Overview

The discussion revolves around understanding Bernoulli's principle, specifically why the pressure across a restriction in a fluid varies as the square of the velocity. Participants seek a conceptual explanation rather than a mathematical one, exploring the relationship between kinetic energy, potential energy, and fluid dynamics.

Discussion Character

  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants assert that Bernoulli's principle is based on the conservation of energy, where kinetic energy is proportional to the square of the velocity and potential energy relates to pressure differences.
  • Others express frustration that the explanations provided do not adequately address the conceptual understanding they seek, emphasizing the importance of understanding "why" rather than relying solely on mathematical formulations.
  • One participant notes the challenge of engaging with another who seems to prefer argumentation over constructive dialogue, suggesting a lack of clarity in the responses given.

Areas of Agreement / Disagreement

Participants generally do not agree on the adequacy of the explanations provided. There is a clear division between those who feel the need for a deeper conceptual understanding and those who focus on the mathematical aspects of the principle.

Contextual Notes

Some participants indicate that the discussion lacks a resolution, with ongoing confusion about the explanations offered and the nature of the inquiry itself.

chevywaldo
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TL;DR
Can someone explain to me Bernoulli's principle as to why the pressure across a restriction varies as the square of the velocity? I'm looking for an understanding (conceptual) as to why this is without a gazillion math examples please. Thanks.
Can someone explain to me Bernoulli's principle as to why the pressure across a restriction varies as the square of the velocity?

I'm looking for an understanding (conceptual) as to why this is without a gazillion math examples please. Thanks.
 
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chevywaldo said:
Can someone explain to me Bernoulli's principle as to why the pressure across a restriction varies as the square of the velocity? I'm looking for an understanding (conceptual) as to why this is without a gazillion math examples please. Thanks.
Bernoulli's principle is simply conservation of energy, of a small mass of fluid.

Kinetic energy is proportional to velocity squared.
Potential energy is proportional to pressure difference.

In physics, follow the energy, as it changes form.
 
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That doesn't answer the question.

Yes I can explain it using math myself, but that's not the point.

Sometimes in physics it's necessary (and often more useful) to understand "why" something happens instead of using only math to show explain. If you only use math to understand physics then you really don't have a full understanding of the principles of why something is or isn't.
 
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And sometimes there isn't. What sort of answer are you looking for?
 
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chevywaldo said:
That doesn't answer the question.

Yes I can explain it using math myself, but that's not the point.

Sometimes in physics it's necessary (and often more useful) to understand "why" something happens instead of using only math to show explain. If you only use math to understand physics then you really don't have a full understanding of the principles of why something is or isn't.
He... didn't use math. I am very confused by your response.
 
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chevywaldo said:
it's necessary (and often more useful) to understand "why" something happens

 
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boneh3ad said:
He... didn't use math. I am very confused by your response.
Having seen earlier posts by chevywaldo, I knew that he liked to argue, and needed to be seen to be proved right. So I was very careful to answer this question, using only the mathematical words that he had used in his OP.

It has been a week since he cast his baited hook into PF, and I carefully pinched his bait. He had warned us that he had a gazillion mathematical barbs on his hook. I believe he has now gone off in frustration, to some other fishing hole under a bridge, where he can play at being a more successful troll.
 
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Thread closed temporarily for Moderation...
 
A very insulting post by the OP has been deleted, and OP is on a 10-day vacation from PF. This thread will remain closed. Thanks everybody for trying to help the OP with their question.
 
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