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prescribe a Womersley flow as boundary condition using CBCflow

+1 vote

Hi,
I am using the code from the fenics cbc flow to prescribe a Womersley flow at the inlet of my mesh (a tube). I can't get a result because I don't know how to write it. From the cbc flow files I can't know what the return of the make_womersley_bcs function looks like.

I understand that this function create the womersley object but how can I use it then to prescribe the flow on my boundary ?

this is a part of my code :

# define the inflow Womersley profile
womersley= make_womersley_bcs(coeff, mesh, inlet, nu, None, boundaries)

for uc in womersley:
    uc.set_t(1/omega)

print("-"*10+" INLET : Womersley flow ")

I tried like this for the Dirichlet Boundary condition

# assign inflow velocity boundary condition
bcu_inflow = DirichletBC(V,Expression(('xdir','ydir','zdir'),xdir=womersley[0],ydir=womersley[1],zdir=womersley[2],degree=2), boundaries, inlet)  

The program does not crash but I dont have any value for my velocity. the solution array is full of "nan".

If someone can help, maybe have already had this problem ...
Thanks

asked May 31, 2017 by Maryama FEniCS Novice (130 points)
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