Setting up Boundary Conditions

The boundary types are already set up in the starting simulation file that you imported at the beginning of the simulation. Here, you associate the inflow boundary condition with a corresponding field function.

By specifying an inlet velocity at the boundary in front of the helicopter, you produce a flow relative to the stationary helicopter body.
The inlet velocity is calculated from:
vInlet=μvTip
(5260)

where μ=vInlet/vTip is the advance ratio and vTip is the tip velocity of the rotor.

  1. Edit the Regions > Wind Tunnel > Boundaries > Inlet > Physics Values node and set the following properties:
    Node Property Setting
    Velocity Magnitude Method Field Functions
    Scalar Function Inlet Velocity
The virtual wind tunnel must not impose floor or ceiling effects on the flow surrounding the fuselage. To model this, you specify a slip condition at these boundaries.
  1. Multi-select the Ceiling and Floor nodes, right-click on any selection and select Edit....
  2. Select the Physics Conditions > Shear Stress Specification node and set Method to Slip.
  3. Click Close and save the simulation.