Hi

I am simulating the flow in a pipe using incompressible cylindrical 2D Navier-Stokes velocity-pressure formulation. I am applying the projection method to solve Poisson pressure equation (Chorin 1968):

[1/r]dP/dr + d²P/dr² + d²P/dz² = f(Uz*,Ur*)

the following boundary conditions are right?

Inflow (z=0): Uz(0,r) = 3 , Ur(0,r) = 0 , dP/dz = 0

Outflow (z=L): dUz/dz = 0 , Ur(0,r) = 0 , P(L,r)= 0

Center (r=0): dUz/dr = 0 , Ur(z,0) = 0 , dP/dr = 0

Wall (r=R): Uz(z,R) = 0 , Ur (z,R) = 0 , dP/dr = 0

Inflow (z=0): Uz(0,r) = 3 , Ur(0,r) = 0 , dP/dz = 0 Outflow (z=L): dUz/dz = 0 , Ur(0,r) = 0 , P(L,r)= 0

You may want to use following,

Inflow (z=0): Uz(0,r) = 3(R+r)(R-r)/R^2 , Ur(0,r) = 0 , dP/dr = 0 because Ur(0,r) = 0 Outflow (z=L): d^2Uz/dz^2 = d^2Ur/dz^2 =d^2P/dz^2 = 0