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## Turbulence in pipe flow

Posted May 11, 2012, 9:43 AM EDT Fluid, Computational Fluid Dynamics (CFD), Mesh Version 4.2a, Version 4.3b 11 Replies

Hi,

I am studying the Navier Stokes equation in the context of pipe flow. As of now, I am using Water, modeling it as incompressible, with outlet at 0 Pa and a parabolic inlet profile. (currently at 2D, but moving to 3D as things advance).

I am currently using Fluid Flow>Single-Phase Flow>Laminar Flow, as my inlet is a stable velocity profile and the turbulence, if any, will arise due to obstacles inside the pipe.

I have been playing with it, doing the Von Karman vortexes simulation (www.comsol.com/showroom/gallery/361/), looking into a moving mesh (www.comsol.com/showroom/gallery/361/), as my object might be able to move subjected to the flow.

My question is: how far can I push the Laminar Flow module? I am looking for turbulence, so I don't think I should be using a Turbulence specific model (it forces turbulence, and requires me to input parameters specific for turbulence, that clearly doesn't exist at the start). On the other hand, I don't know if the Laminar Flow module will be able to propely simulate turbulence.

What should I be using then?

Thank you for input.

I am studying the Navier Stokes equation in the context of pipe flow. As of now, I am using Water, modeling it as incompressible, with outlet at 0 Pa and a parabolic inlet profile. (currently at 2D, but moving to 3D as things advance).

I am currently using Fluid Flow>Single-Phase Flow>Laminar Flow, as my inlet is a stable velocity profile and the turbulence, if any, will arise due to obstacles inside the pipe.

I have been playing with it, doing the Von Karman vortexes simulation (www.comsol.com/showroom/gallery/361/), looking into a moving mesh (www.comsol.com/showroom/gallery/361/), as my object might be able to move subjected to the flow.

My question is: how far can I push the Laminar Flow module? I am looking for turbulence, so I don't think I should be using a Turbulence specific model (it forces turbulence, and requires me to input parameters specific for turbulence, that clearly doesn't exist at the start). On the other hand, I don't know if the Laminar Flow module will be able to propely simulate turbulence.

What should I be using then?

Thank you for input.

11 Replies Last Post May 14, 2014, 9:45 PM EDT