Power law viscosity
 

how can one enter a power law viscosity relation in Ansys Fluent :)

Hi. Fluent has non newtonian power law viscosity model and you don't need to write a udf for it.just go to material and choose non newtonian powerlaw viscosity from viscosity tab and inter power law index (n) and K and 2 other parameters. This parameters depend on material properties. Also you can write a udf for it. Do you want write udf for it?

Fluent non newtonian
 

Ok, Thanks!
What is the refrence value the programme is taking to calculate drag,or lift and other values ,say for K=1,n=1.8 and some limit of viscosity.
Can u help me write a progamme?

Unfurtunetly, I don't know the relation between powerlaw viscosity and calculating drag or lift.

For post-processing, such as calculating force and moment coefficients, Fluent will use the reference values you specified in the Reference Values panel.

How can i do an isothermal simulation using fluent model for power law viscosity? It requires some parameters of temperature.

Use a constant viscosity. Calculate what this viscosity is using power law separately on your phone or whatever.