Rob
Forum Moderator

How does the mass flux balance look?  Turn off auto range on the contour plot, turn on filled and expand the scale (range) by a small amount at each end (so 0 to 5ms would be -0.01 to 5.01m/s).  The porous region won't slow/accelerate the flow (read the theory) but equally shouldn't stop it unless the flow can bypass the porous zone. 

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