[sina_mech]

I am solving a problem, which includes a pressure inlet (the average pressure is fixed at inlet and zero-gradient velocity). The inlet is a pipe, so there is no-slip boundary condition on its wall.

The issue is that it seems that the no-slip boundary condition of the wall at inlet is ignored by zero-gradient condition of the inlet! so the velocity at the perimeter of the circular section of the inlet is not zero! (which theoretically should be). I would appreciate any comment/help on it.
Thanks.

These are the BCs:

VELOCITY:

WALL
    {
        type            fixedValue;
        value           uniform (0 0 0);
    }

FLOW_in
    {
        type            zeroGradient;
    }


PRESSURE: 

FLOW_in
    {
        type            zeroGradient;
    }

WALL
    {
     type            fixedMeanValue;
    meanValue        100000;    
        value           uniform 100000;
    
    }

[sina_mech]

any help or comment? :-)

[jherb]

You might want to take a look at the totalPressure boundary condition.

[chegdan]

Just to add a little to what JHerb is asking....use a zeroGradient pressure at the walls rather than a fixedMean like you have done.