[CeesH]

Hello all,

I have a question related to non-newtonian fluids and turbulence. I know how to enable the model, but I cannot find in the FLUENT manual what the option 'enable turbulence for non-newtonain fluid' actually does (and what happens if you run a turbulence model + non-newtonian fluid without enabling this option)

Does enabling the option mean that the effect of the fluctuating strain rate is also included in determining the effective viscosity? Or will only the mean strain rate be included? If so, what is the difference with not enabling the non-newtonian turbulence option? Because when I leave it off, I do still get reasonable viscosity profiles in the domain and also the velocity profile is clearly affected.

Best regards
Cees

[CeesH]

It seems there are no ideas?

[ghost82]

Hi Cees,
if you didn't already read this:

http://rheology-esr.net/Open_transac...20Karvinen.pdf

you can find some info starting on page 3 about turbulence for non newtonian fluids.
Maybe it is part or what you're looking for.

[CeesH]

Hi Daniele,
I did not look at that yet no - so far I was trying to figure out the specific implementation in FLUENT. Thanks, I'll check it out!

[ghost82]

I read the article fast, but at the end it seems it's related to polyflow (laminar simulations) and fluent (turbulence); so the description should be relevant to fluent, even if it was a very old version.
Maybe it can be usefull to start searching for other sources.