Dear Firedrakers,

I've been trying to implement 0 dirichlet boundaries on a mixed function space that includes a vector space

#Set up boundary conditions

bcv_x = DirichletBC(W.sub(0).sub(0), Constant(0), method="geometric")

bcv_z = DirichletBC(W.sub(0).sub(1), Constant(0), method="geometric")

but I get back

AttributeError: 'VectorFunctionSpace' object has no attribute 'sub'

I thought we were meant to use sub twice to refer first to the function space component and then to the vector component.

Also, would this be a correct approach for implementing no normal flow boundaries or is there a more appropriate method to use.
Thanks

Will