# Problem with finding the boundary

Hello,

Ive tried to define the inner circle of a tire as a dirichlet boundary like that:

def Restboundary2(

tol = 1E-6

return on_boundary and sqrt(x[

u_i=Constant(

bci=DirichletBC

with 0.22 the inner radius.

when i start solving i get the error:

"Found no facets matching domain for boundary condition."

when i try the same with a neumann boundary

class NeumannBoundary

def inside(self, x ,on_boundary):

tol = 1E-6

return on_boundary and sqrt(x[

boundary_parts= MeshFunction(

boundary_

nm_boundary2=

nm_boundary2.

and plot the boundary parts i can see that it finds the boundary as i want it.

so does anybody has an idea whats wrong??

thanks

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- Anders Logg

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