Fluid Mechanics- Bernoulli Equation

AI Thread Summary
The discussion centers on the application of the Bernoulli Equation to non-uniform flows, particularly regarding the velocity profile of water exiting a pipe with a parabolic velocity profile into a free jet. Participants debate whether the velocity profile remains parabolic or becomes uniform at the exit, noting that there are no forces to accelerate or decelerate the water. One contributor argues that the flow path changes when the fluid leaves the orifice, which could affect the velocity profile. Another emphasizes the assumption of incompressibility in the analysis. Ultimately, the conversation highlights the complexities of fluid dynamics in this scenario.
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The Bernoulli Equation for non-uniform flows have a constant at the kinetic energy term which describes the velocity profile at that place. The problem is this, If a have water flowing through a pipe with a parabolic velocity profile and then the water exit the pipe at free jet and there is now friction due to air, what would be the velocity profile at the free jet area, uniform or parabolic?
There is nothing in between these two points that would accelerate or deccelerate water.

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I don't think there is a simple formula for that, sorry. You have two complex fluids moving relative to each other.
 
Cyrus said:
I don't think there is a simple formula for that, sorry. You have two complex fluids moving relative to each other.

There is no friction from the air on the water.

Here is what I think, since there is nothing that would affect the velocity profile of the water, water would continue to have a parabolic profile. But that's what I think, what do you guys think?
 
No that's not true. When a fluid leaves an orifice its flowpath changes. It can expand or contract at the exit.
 
Ok then, that's very true but let assume that water is incompressible.
 
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