Solving 3D Compressible NS for Cylindrical Pipe

AI Thread Summary
The discussion focuses on converting three-dimensional unsteady compressible Navier-Stokes equations into a two-dimensional incompressible form for a cylindrical pipe. Participants emphasize the need for the original poster to follow forum guidelines and provide their own attempts at the solution. Key steps include using cylindrical coordinates, eliminating transient terms, and considering the implications of density and divergence on the mass equation. Questions are raised about the velocity components and boundary conditions necessary for deriving the streamwise velocity profile. Overall, the conversation highlights the collaborative nature of problem-solving in fluid dynamics.
pasta
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Can somebody provide a solution for this question?
convert 3 dimensional unsteady compressible NS equations to axisymmetric 2 dimensional incompressible laminar form for a cylindrical pipe, then make a derivation of streamwise velocity profile u(r) using the appropriate boundary conds.

thanks
 
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Helllo pasta, :welcome:

Unfortunately (in first order) this is not the way PF works. You can get expert help but you have to make an effort yourself as well: read the guidelines and use the template; then we can help you.

1. Homework Statement 2. Homework Equations 3. The Attempt at a Solution​
 
This homework problem was originally posted in another forum so there is no template
BvU said:
Helllo pasta, :welcome:

Unfortunately (in first order) this is not the way PF works. You can get expert help but you have to make an effort yourself as well: read the guidelines and use the template; then we can help you.

1. Homework Statement 2. Homework Equations 3. The Attempt at a Solution​

use cylindrical coordinates equations
zero out all of the transient terms, take the limit as the density goes to a constant and div U goes to zero.
mass equation will collapse to div U = 0

once I've calncelled. what do i do?
 
Can you share the equation that you have derived? Then we can help you point out where it went wrong or help you on the next step.
 
pasta said:
use cylindrical coordinates equations
zero out all of the transient terms, take the limit as the density goes to a constant and div U goes to zero.
mass equation will collapse to div U = 0

once I've calncelled. what do i do?
Which velocity components are zero, and which velocity components are not zero? Take that into account. What about the acceleration terms? Is the flow accelerating? What about the boundary conditions on velocity? What is the velocity at the wall?

Chet
 
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