[ssc0109]

Hello All,
I just recently found some issues while using openFOAM.
Here is the test example: a flow through a 2D pipe

I just modified the simplefoam with a source term S added to the UEqn.H
where S is a volume vector field which equations 10 in the y direction (and 0 in others).

Now I check the velocity and pressure field over the white arrow in the figure


For the pressure, on the top and bottom wall, I used 0 gradient bc,
but the pressure gradient is not 0


for the velocity in y direction, you can see there is a oscillation.


well, since I need the gradient of the velocity on the wall, this gives me trouble.

Any idea how to make the velocity more smoother?