Step 2: General Settings

General

1.   Check the mesh.

General Check

   ANSYS FLUENT will perform various checks on the mesh and will report the progress in the console. Ensure that the reported minimum volume is a positive number.

  Warnings will be displayed regarding unassigned interface zones, resulting in the failure of the mesh check. You do not need to take any action at this point, as this issue will be rectified when you define the mesh interfaces in a later step.

2.   Examine the mesh (Figure  12.2).

  Orient the view to display the mesh as shown in Figure  12.2. The inlet of the rotor mesh is colored blue, the interface between the rotor and stator meshes is colored yellow, and the outlet of the stator mesh is colored red.

Figure 12.2: Rotor-Stator Display

3.   Use the text user interface to change zones rotor-per-1 and rotor-per-3 from wall zones to periodic zones.

(a)   Press $<$ Enter $>$ in the console to get the command prompt ( $>$).

(b)   Type the commands shown in green as follows:

> mesh

/mesh> modify-zones

/mesh/modify-zones> list-zones

  id  name                       type                material              kind
----  -------------------------  ------------------  --------------------  ----
  13  fluid-rotor                fluid               air                   cell
  28  fluid-stator               fluid               air                   cell
   2  default-interior:0         interior                                  face
  15  default-interior           interior                                  face
   3  rotor-hub                  wall                aluminum              face
   4  rotor-shroud               wall                aluminum              face
   7  rotor-blade-1              wall                aluminum              face
   8  rotor-blade-2              wall                aluminum              face
  16  stator-hub                 wall                aluminum              face
  17  stator-shroud              wall                aluminum              face
  20  stator-blade-1             wall                aluminum              face
  21  stator-blade-2             wall                aluminum              face
  22  stator-blade-3             wall                aluminum              face
  23  stator-blade-4             wall                aluminum              face
   5  rotor-inlet                pressure-inlet                            face
  19  stator-outlet              pressure-outlet                           face
  10  rotor-per-1                wall                aluminum              face
  12  rotor-per-2                wall                aluminum              face
  24  stator-per-2               wall                aluminum              face
  26  stator-per-1               wall                aluminum              face
   6  rotor-interface            interface                                 face
  18  stator-interface           interface                                 face
  11  rotor-per-4                wall                aluminum              face
   9  rotor-per-3                wall                aluminum              face
  25  stator-per-4               wall                aluminum              face
  27  stator-per-3               wall                aluminum              face

/mesh/modify-zones> make-periodic

Periodic zone [()] 10

Shadow zone [()] 9

Rotational periodic? (if no, translational) [yes] yes

Create periodic zones? [yes] yes


  all 176 faces matched for zones 10 and 9.
    zone 9 deleted
     created periodic zones.

4.   Similarly, change the following wall zone pairs to periodic zones:

Zone Pairs	Respective Zone IDs
rotor-per-2 and rotor-per-4	12 and 11
stator-per-1 and stator-per-3	26 and 27
stator-per-2 and stator-per-4	24 and 25

5.   Define the solver settings.

General

(a)   Select Density-Based in the Type list.

(b)   Select Transient in the Time list.

6.   Define the units for the model.

General Units...

(a)   Select angular-velocity from the Quantities selection list.

(b)   Select rpm from the Units selection list.

(c)   Select pressure from the Quantities selection list.

  Scroll down the Quantities list to find pressure.

(d)   Select atm from the Units selection list.

(e)   Close the Set Units dialog box.