Fluid mechanics, source-sink question

Thread starter liometopum
Start date Jul 19, 2013
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Fluid Fluid mechanics Mechanics

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In fluid mechanics, the velocity of liquid entering or exiting a hole in a two-dimensional model is expressed as Q/(2 pi r). The discussion raises a question about the velocity in three dimensions, suggesting it may be Q/(4 pi r^2) for a point source. This formulation is confirmed as correct for three-dimensional scenarios. The conversation highlights the differences in fluid flow modeling between two and three dimensions. Understanding these principles is essential for accurate fluid dynamics analysis.

Jul 19, 2013

liometopum

In fluid mechanics, the velocity of the liquid going in or out (source-sink) of a hole in a two dimensional model is Q/(2 pi r). http://farside.ph.utexas.edu/teaching/336L/Fluidhtml/node63.html

What is the velocity in three dimensions? Is it Q/(4 pi r^2) ?

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Jul 20, 2013

Curl

For a point source, correct.

Jul 21, 2013

liometopum

Thank you, Curl!

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