[Choni]

Hi, everyone!
I'm new member in OpenFOAM, currently simulating a stationary incompressible flow in a Tesla valve.
Repeating the geometry (valve+2 cylinders) from the experimental article(https://www.mdpi.com/2072-666X/13/8/1180), I simulate the movement of the liquid and compare the pressure obtained with the results. But they don't add up.
There was a hypothesis that it was necessary to grind the grid, but this does not help: I got to the difference of 2% between the simulation results, it seems to me that there is no point in grinding further.
The results are still 2-3 times less than expected.
I tried to take the articles that these scientists took as a basis, but still the results are much less. I multiply the resulting pressure by the density of the liquid, because I use incompressible solver.

I wrote the boundary conditions below, but I don't see any errors in them:
Velocity:

FoamFile
{
    version     2.0;
    format      ascii;
    class       volVectorField;
    object      U;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform (0 0 0);

boundaryField
{	
	inlet
    {
        type            fixedValue;
        value           uniform (-1.25 0 0);
    }

    outlet
    {
        type            zeroGradient;
    }

    wall
    {
        type            noSlip;
    }

    front
    {
        type            noSlip;
    }
	
	back
    {
        type            noSlip;
    }
	
}

// *************************************************************************

And pressure:

FoamFile
{
    version     2.0;
    format      ascii;
    class       volScalarField;
    object      p;
}
// * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * //

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

internalField   uniform 0;

boundaryField
{
    inlet
    {
        type            zeroGradient;
    }

    outlet
    {
        type            fixedValue;
        value           uniform 0;
    }

    wall
    {
        type            zeroGradient;
    }

    front
    {
        type            zeroGradient;
    }
	
	back
    {
        type            zeroGradient;
    }

}

Please, hepl me, if you know why the results don't add up