[highhopes]

Hello everyone,

I am having some issues with my 2D axisymmetric model. I am trying to get a constant temperature average on a heated pipe interior wall exposed to oscillating flow.

Imagine a long pipe with porous region covering 1/7 of the pipe in the middle. The wall of the porous part is heated by introducing constant heat flux. The fluid, water in this case, is oscillated with a low frequency. The domain is also cooled down through the remaining surface.

However, the cooling cannot set a balance and the wall temperature keeps increasing even though the axial temperature gradient right outside the foam is extremely high.

I have been using RNG k-epsilon with enhanced wall treatment (y+ around 0.8) and PISO as the pressure-velocity coupling.

I think that the mixing is not effective enough. Is there an option you would recommend mixing-related? Or is there any detail that needs to be known about solving convection-diffusion problems with Fluent.

I would appreciate any kind of help.

Thank you

[vishnuktm]

I am doing a similar work on thermoacoustic refrigerator. How do you create a low freq oscillation. Can you please explain.

[highhopes]

I introduced sinusoidal functions with the desired frequencies as user defined velocities at both ends. They had different signs, but same magnitudes.

[highhopes]

Could anyone point me to a viable finite volume study on oscillatory heat transfer? Because I haven't found a solution so far.
And, is there a way to save the hydrodynamic data at each time step in order to avoid calculation every oscillation cycle so that fluent will only solve the energy equations?

[sache]

Originally Posted by vishnuktm

I am doing a similar work on thermoacoustic refrigerator. How do you create a low freq oscillation. Can you please explain.

Hey,
have you got the answer,