Specify the Physics Behavior

Specify the physics behavior of the air flowing around the drone.

The physics behavior of fluid flow includes the effects of various environmental conditions on a fluid, as well as the innate physics behaviors of the fluid itself. For example, you can specify the impact of radiation, gravity, and heat on fluid flow. You can also specify if a fluid is compressible or incompressible.

In this example, you specify a particular turbulence model theory for the air flowing around the drone. There are a number of environmental effects that you can consider, but you ignore these effects for simplicity purposes. Afterward, you define a steady-state step to simulate stable, time-insensitive flow.

  1. From the Physics section of the Assistant, click Physics Behavior .
  2. From the Turbulence model options, select SST k-ω.

    The SST k-ω turbulence model is appropriate for external fluid flow scenarios.

  3. Click OK.
    When you define the physics behavior, the app automatically generates initial conditions with default settings.
  4. From the Physics section of the Assistant, click Steady State Step .
  5. Select Enable auto under-relaxation for all equations.

    This option gradually converges the turbulence equations to the thresholds that you specify in the Stopping Criteria section.

  6. Expand the Stopping Criteria section, and clear all of the check boxes under Error Thresholds.

    Selecting multiple stopping criteria might result in additional iterations as the solvers attempt to satisfy all of them. In this example, you clear the errors thresholds criteria to support faster convergence. Applying only residual thresholds is also a common method for ensuring accurate results at the convergence point.

  7. Click OK.