''matrix dimensions must agree'' in Navier-Stokes models
i have two Navier-Stokes Equations, coupled by the volume force, which is a function of the relative velocity (i.e. Fx = f(u1-u2) and Fy = g(v1-v2)). i receive the error ''matrix dimensions must agree''.
However, while i change the force into a constant, or a function of x and y, there is no error anymore.
pressure is constrained at points, suggested by a previous post here.
I appreciate any clue or discussion.
my settings: time dependent solver, MUMPS + Backward Euler