Setting Solver Parameters and Stopping Criteria

To avoid excessive compute time, you introduce a stopping criteria that stops the simulation when the net thrust in the X direction is close to zero. At that point you know the steady propulsion point has been achieved.

As the purpose of this simulation is to reach a steady state condition (pseudo-transient run) there is no need to obtain tight convergence in each time-step. Hence the number of inner iterations for the transient solver can be reduced, and the number of iterations for the 6-DOF solver.

To set the solver parameters and transient stopping criteria:
  1. Edit the Solvers node and set the following parameters:
    Node Property Setting
    Implicit Unsteady Time-Step 0.02 s
    6-DOF Solver Maximum Number of Iterations 3
  2. Edit the Stopping Criteria node and set the following parameters:
    Node Property Setting
    Maximum Inner Iterations Maximum Inner Iterations 5
    Maximum Physical Time Maximum Physical Time 50.0 s
    Maximum Steps Enabled Deactivated
  3. To add a stopping criterion that checks for the net longitudinal force reaching zero:
    1. Right-click the Stopping Criteria node and select New Monitor Criterion.
    2. In the Select Monitor dialog, choose X Component of Net Force Monitor and click OK.
    3. Edit the X Component of Net Force Monitor Criterion node and set the following properties:
      Node Property Setting
      X Component of Net Force Monitor Criterion Criterion Option Minimum
      Stop Inner Iterations Deactivated
      Minimum Limit Minimum Value 0.1
  4. Save the simulation.