[mpml]

Hi,

First, I would like to thank FOAM developers for this wonderful code. I am looking at the transport models you defined for non-Newtonian fluids, namely, the CrossPowerLaw and the BirdCarreau. I find that both models have 4 parameters in them, nu0, nuInf, m, and n.

According to what I know, the PowerLaw for polymer is expressed as "eta=m*gamma^(n-1)", where eta is the viscosity(unit: Pa.s), gamma is the shear rate(1/s).

In addition, CrossCarreau model is expressed as "(eta-eta0)/(eta-etaInf)=(1+(lambda*gamma)^a)^((n-1)/a)", where eta0 and etaInf are the zero and infinite shear viscosity(Pa.s), gamma is the shear rate(1/s), lambda a time constant, a=2 is a coeffecient, and n is the same as in Powerlaw.

I believe the above models have been transformed into some other forms, so could you explain the meaning of nu0, nuInf, m, and n in OpenFOAM, as opposed to the standard definition?

Also, I find that the sample program for nonNewtonianIcoFoam has a very low material viscosity, do you think it will be a problem if I increase the viscosity to the order of 10^3-10^6?

Thanks very much.