When running the Demo for Navier-stokes in python, the following error comes up. How can I fix this to make the code run? I want to use it as an example to build a different fluid dynamics code.
Also, what will this demo export in terms of properties (i.e. pressure, water velocity, ect.)?
Error:
C:\FEniCS\share\dolfin\demo\pde\navier-stokes\python>python demo_navier-stokes.p
y
Computing tentative velocity
*** Warning: Requested preconditioner is not available for uBLAS Krylov solver
. Using ILU.
Solving linear system of size 15170 x 15170 (uBLAS Krylov solver).
Krylov solver converged in 0 iterations.
Computing pressure correction
Traceback (most recent call last):
File "demo_navier-stokes.py", line 114, in
solve(A2, p1.vector(), b2, "gmres", "amg")
File "C:\FEniCS\lib\site-packages\dolfin\fem\solving.py", line 254, in solve
return cpp.solve(args)
File "C:\FEniCS\lib\site-packages\dolfin\cpp.py", line 20119, in solve
return _cpp.solve(args)
RuntimeError:
*** -------------------------------------------------------------------------
*** DOLFIN encountered an error. If you are not able to resolve this issue
*** using the information listed below, you can ask for help at
*** https://answers.launchpad.net/dolfin
*** Remember to include the error message listed below and, if possible,
*** include a minimal running example to reproduce the error.
*** -------------------------------------------------------------------------
*** Error: Unable to solve linear system using Krylov iteration.
*** Reason: Unknown preconditioner "amg". Use list_krylov_solver_preconditioners
() to list available preconditioners().
*** Where: This error was encountered inside KrylovSolver.cpp.
*** -------------------------------------------------------------------------
