Defining a Steady-State Flow Step

You can define a steady-state flow step to perform a fluid dynamic analysis on a system that does not depend on time.

  1. From the Procedures section of the action bar, click Steady State Step .
  2. Optional: Enter a descriptive Name.
  3. Enter a value for the Maximum iterations for the simulation.

    The step stops if this maximum is exceeded before the solvers arrive at the complete solution for the step.

    By default, steady-state flow steps run for a maximum of 2000 iterations.

  4. For incompressible flow simulations, determine how you want to specify the under-relaxation factor for the equations in the simulation:
    • Select Enable auto under-relaxation for all equations, which defines the under-relaxation factor automatically for all equations.
    • Clear Enable auto under-relaxation for all equations, and specify the under-relaxation factor manually in each applicable equation controls section.

    For more information about under-relaxation factors, see About Under-Relaxation Factors.

  5. Expand the Stopping criteria section to define one or more conditions that, when all conditions are satisfied, prompt the app to end the step's iterations.

    For more information, see Specify Stopping Criteria.

  6. Optional: Specify the equation controls for each equation required by your steady-state flow step.

    For more information, see Equation Controls.

  7. Optional: Expand the Expert numerics controls section to specify the analysis behavior for disabling secondary diffusion and second-order advection.

    Disabling secondary diffusion and second-order advection can help the solver converge in situations when it might not otherwise; however, the solution might be less robust.

    For more information, see Defining Expert Numerics Controls.

  8. Optional: Expand the Expert cycle controls section to freeze the flow field or energy field during simulation.

    Freezing the flow field or energy field deactivates the corresponding equation solvers, thereby saving simulation time.

    For more information, see Freezing the Flow Field and Energy Field.

  9. Optional: Select Enable particle modeling to simulate the motion of Lagrangian particles in the fluid physics, and then expand the Particle modeling parameters section to specify the type, material, and behavior for the particles.

    For more information, see Defining Particle Controls.

  10. Click OK.