[FlyBob91]

Hello to all,
I need to calculate the passive scalar in a duct after running a steady simulation to obtain the velocity field.
My geometry consists in a duct with two inlets and what i have to do is to calculate the concentration field of the fluids. For this reason, in the T boundary condition file, i put unitary value on the first inlet and a null value on the second inlet for T.

imensions      [0 0 0 1 0 0 0];

internalField   uniform 0;

boundaryField
{

    inlet1
    {
        type            fixedValue;
        value           uniform 1;
    }

    inlet2
    {
        type            fixedValue;
        value           uniform 0;
    }

    outlet
    {
        type            zeroGradient;
    }

    walls
    {
        type            zeroGradient;
    }

    mouvable
    {
        type            zeroGradient;
    }

}

After running the simulation i've found that T assumes, in some regions, values below to zero and over to one. Any idea about this problem?

The second doubt i have is about the fact that the first simulation to find the velocity field is unsteady, while i calculated the passive scalar with an unsteady simulation. Is this a correct procedure or i have to run an unsteady simulation also for the passive scalar?


Thanks for help