Why Does Increasing Velocity Decrease Pressure in Fluid Dynamics?

AI Thread Summary
Increasing velocity in fluid dynamics leads to a decrease in pressure due to the principles outlined in Bernoulli's equation, which states that the sum of static pressure, gravitational potential energy per unit volume, and dynamic pressure remains constant along a streamline. While dynamic pressure increases with velocity, the overall pressure decreases as the fluid accelerates, illustrating the conservation of energy in fluid flow. The discussion also clarifies that when manipulating Bernoulli's equation, the term should refer to change in gauge pressure, as it aligns with the changes in other variables like height and velocity. Understanding these relationships is crucial for grasping fluid dynamics concepts. The interplay between velocity and pressure is fundamental in fluid mechanics.
Wombat11
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This Is more of a conceptual question. If the equation for dynamic pressure is 1/2(density)(velocity)^2 then as velocity increases the pressure would also, but I was told that as velocity increases pressure decreases. If anyone could explain this to me that would be great.
 
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As an isolated term, your description of the relationship between dynamic pressure and velocity would be correct. But you will find that as applied to fluid flow there are conservation laws that tie it to other quantities.

Take a look at the Bernoulli equation.
 
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In Bernoulli's equation is it pretty much saying that (static/gauge pressure)+ (pressure due to change in height)+(dynamic pressure) is a constant? Also my teacher manipulated the equation so it was Gauge pressure=(d)(g)(change in height)+ 1/2(d)(change in velocity)^2. Would it be Gauge pressure or change in Gauge pressure? Thanks.
 
Wombat11 said:
In Bernoulli's equation is it pretty much saying that (static/gauge pressure)+ (pressure due to change in height)+(dynamic pressure) is a constant?
Along a streamline, yes.
Also my teacher manipulated the equation so it was Gauge pressure=(d)(g)(change in height)+ 1/2(d)(change in velocity)^2. Would it be Gauge pressure or change in Gauge pressure? Thanks.
I would think it would be change in gauge pressure, since the other terms are changes.
 
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