[slugger]

Hi everyone.

I am running a simulation of air being pushed at high speed through a narrow opening. I use a high pressure at the inlet and ambient pressure at the outlet to drive the flow. To ensure that the simulation does not immediately crash due to poor initial pressure and velocity conditions, I start the simulation with a very high viscosity. I am using the Sutherland transport model with

transport
{
Pr 0.7;
As 1.4792e-02; // really should be 1.4792e-06
Ts 113;
}

As you can see, the coefficient As is 10^4 times as large as it should be, and this ensures that the simulation behaves properly.

I would like to be able to change the coefficient As as the simulation runs. I know this is possible for the quantities at the boundaries, I am already doing this for the pressure at the inlet, which I slowly increase from 1bar to 4.5bar, but I cannot seem to find any info on how I should dynamically change the thermo properties.

Thanks,
Teun