dolfin team mailing list archive

[Johan Hake <johan.hake@xxxxxxxxx>]

Please provide the version of DOLFIN you are using and the output of what 
DOLFIN tells you when you actually run the code. If you also provide a minimal 
runnable code snippet that would also be very useful!

Johan

On Monday January 10 2011 10:00:04 B. Emek Abali wrote:
> New question #140910 on DOLFIN:
> https://answers.launchpad.net/dolfin/+question/140910
> 
> setting a mixed space (velocity field v, pressure field p) as
> 
> V = VectorFunctionSpace(mesh, 'CG', 1)
> Q = FunctionSpace(mesh, 'DG', 0)
> ME = MixedFunctionSpace([V,Q])
> 
> and by describing
> 
> null = Constant(0.0)
> class TopDrag(Expression):
> 	def eval(self, vec, x):
> 		vec[0] = 10.0
> 		vec[1] = 0.0
> 		vec[2] = 0.0
> 	def dim(self):
> 		return 3
> 
> vOnTop = TopDrag()
> 
> wanted to reach:
> 
> a given velocity on a subdomain (not here but defined in a proper way with
> compile_subdomains() ) DirichletBC(ME.sub(0), vOnTop, top)
> 
> zero velocity in one direction
> DirichletBC(ME.sub(0).sub(1), null, front)
> 
> and a given pressure on a subdomain
> DirichletBC(ME.sub(1), pIn, left)
> 
> which I couldn't :)
> 
> Any sharp eyes where I am not thinking as FEniCS wants?