Should be available

http://www.cfd-online.com/Forums/fluent/40645-non-newtonian-fluid-fluent.html

depends on the model you are looking for though

Hi Asr,

You are in fact able to model turbulent non-Newtonian flows in ANSYS Fluent using either the available sub-models or with a User Defined Function approach. The turbulence models will be used to compute the turbulent viscosity while the non-Newtonian flow models will be used to compute a Strain dependent dynamic viscosity. The two models are perfectly compatible in FLUENT.

Hi Mahdi,

Below is an example of a UDF based on the Quemada blood viscosity model:

#include "udf.h"

#define mu_p 0.00123

#define H_ct 0.48

#define k_0 3.96

#define k_inf 1.71

#define gamma_c 5.0

DEFINE_PROPERTY(cell_viscosity,c,t)

{

real shear_rate;

real mu;

real k;

real sqrt_gamma_ratio;

shear_rate = C_STRAIN_RATE_MAG(c,t);

sqrt_gamma_ratio = sqrt(shear_rate/gamma_c);

k = (k_0+k_inf*sqrt_gamma_ratio)/(1+sqrt_gamma_ratio);

mu = mu_p/pow((1-0.5*k*H_ct),2);

return mu;

}

Hope this helps.

Regards,

Haitham

Dear Mahabi, when it comes to turbulence in non-Newtonian fluids, there is no physically consistent turbulence model yet. What Fluent does, is replacing the molecular viscosity with the apparent one in the RANS equations. This is wrong fro a number of reasons. Above all, the rms of the shear rate its much higher than its mean, so the mean apparent viscosity is not the apparent viscosity calculated at the mean shear rate. Anyway, as I said, there is no consistent model so far. I Suggest you to read the works of Pinho, Gavrilov and myself (in particular: 

http://www.sciencedirect.com/science/article/pii/S073519331100039X

http://www.sciencedirect.com/science/article/pii/S0735193312000371

) for a deep discussion. Kind Regards

Navier-Stokes equations: this is the basis for fluid flow modeling, to summarize, download articles on non-Newtonian fluids and just follow examples given.

Thanks my friends for making such a valuable contribution.

https://www.sciencedirect.com/search?qs=model%20non-Newtonian%20fluid%20flows&show=25&sortBy=relevance

It is available in Ansys customer portal

https://support.ansys.com/AnsysCustomerPortal/en_us/Knowledge+Resources/Solutions/FLUENT/2048595