[parthigcar]

Dear community,

I am very new to OpenFOAM as well as to CFD. I am trying to simulate pressure-driven flow (geometry is similar to an inverted L shape, where the inlet is at the bottom), where we apply time-dependent pressure at the inlet and measuring the mass flow rate at the outlet. While I am able to run the simulation without any error. However, the outlet mass flow rate is 2 orders lower than lumped simulation. Here, I have taken sodium as working fluid (however I assume that wont make any difference, since I have divided the pressure with the sodium density, and provided appropriate viscocity in transport properties.)

I would be grateful if any of you can point out where I am doing wrong. My velocity and pressure boundary is as follows:
Velocity boundary conditions:

dimensions      [0 1 -1 0 0 0 0];


internalField   uniform (0 0 0);

boundaryField
{
    inlet
    {
        type            pressureDirectedInletOutletVelocity;
        inletDirection  uniform (0 0 1);
        value           uniform (0 0 0);
    }
    walls
    {
        type            noSlip;
    }
    wedge1
    {
        type            symmetry;
    }
    wedge2
    {
        type            symmetry;
    }
    top_walls
    {
        type            noSlip;
    }
    outlet
    {
        type            pressureInletOutletVelocity;
        value           uniform (0 0 0);
    }
    interface3
    {
        type            empty;
    }
    interface4
    {
        type            empty;
    }
}

Pressure boundary conditions:

dimensions      [0 2 -2 0 0 0 0];

internalField   uniform 0;

boundaryField
{

    inlet

    {
        type            uniformTotalPressure;

        p0 table
        (
        );
    }


    outlet
    {
        type            totalPressure;
        p0              uniform 0;
        value           uniform 0;
    }

    walls
    {
        type            zeroGradient;
//          type            fixedFluxPressure;
//          value           uniform 0;
    }
    top_walls
    {
        type            zeroGradient;
//          type            fixedFluxPressure;
//          value           uniform 0;
    }
        wedge1
    {
        type            symmetry;

    }
        wedge2
    {
        type            symmetry;

    }
		defaultFaces
		{
		  type empty;
		}
		interface3
		{
		  type empty;
		}
		interface4
		{
		  type empty;
		}
}

Transport properties:

transportModel Newtonian;

// Laminar viscosity
nu              2.16e-04;

// Thermal expansion coefficient
beta           3.0164e-4; 

// Reference temperature
TRef            873;

// Laminar Prandtl number
Pr              0.0044;

// Turbulent Prandtl number
Prt             0.85;