[skuznet]

I'm trying to solve a fluid flow in a porous material problem in Abaqus/CFD using steady-state solver.
When I'm trying to solve it with Abaqus/CFD steady-state solver the CFD Steady State Incompressible Flow Nonlinear Residuals initially decrease and then start oscillating, i.e. v_x and v_z will reduce, while v_z will increase.
After a number of such oscillations v_z abruptly becomes zero, then v_x and v_y become zero and then -nan. I've attached a part (beginning and end) of sta file.

I was able to obtain solution for a simple flow around a cylinder problem with steady-state solver, but can't get solution for my complex domain.

Can any one suggest me how can I obtain the solution? Can changing under-relaxation factors help me with this?

[wisam85]

hi
could you tell me please how did use the steady state solver in abaqus? because i dont know how to choose it.

[skuznet]

Hi! Sorry for late reply, I didn't check this site for long time.
If you still interested in it, in Abaqus you have to do it in input file, for example

*Step, name=Flow, nlgeom=NO
*CFD, incompressible navier stokes, energy equation=TEMPERATURE, STEADY STATE
500
*Momentum Equation Solver
50, 2, 1e-05
*Pressure Equation Solver
250, 2, 1e-05
ICC, 1, 1, CG
*Transport Equation Solver
50, 2, 1e-05