Defining Regions Layout

Two regions are required for this simulation: one for the air and one for the solid components.

The Printed Circuit Board (PCB) exhibits orthotropic thermal conductivity. The multi-part solid model in Simcenter STAR-CCM+ allows you to model orthotropic thermal conductivity in a single region. This region contains all the solid components of the graphics card and the fan casings.

Parts-based interfaces allow you to group related surfaces in a single interface. Grouping similar interfaces together simplifies the simulation setup and can provide performance improvements, especially in cases with large amounts of interfaces. You can automatically create parts-based interfaces when assigning parts to regions.

To create the air region:

  1. Right-click the Geometry > 3D-CAD Models > 3D-CAD Model 1 node and select New Geometry Part...
  2. In the Part Creation Options window, deactivate Create Part Contacts from Coincident Entities and click OK.
    By deactivating the Create Part Contacts from Coincident Entities option the contacts created in 3D-CAD do not get overwritten when the parts are created.
  3. Right-click the Parts > Air Case node and select Assign Parts to Regions.
  4. In the Assign Parts to Regions dialog:
    1. From the Parts list, select Air Case, Air Inlet, and Air Outlet.
    2. Select Create One Region for All Parts and enter Air in the neighboring text box.
    3. Select Create a Boundary for Each Part Surface.
    4. Select Create Contact-mode Interfaces From Contacts.
    5. Click Apply.
    Simcenter STAR-CCM+ creates one region for the selected parts, and separate boundaries for each named surface.
Create a region for all the solid components:
  1. In the same Assign Parts to Regions dialog, select all the parts in the dialog.
  2. Deselect the following parts:
    • Air Case
    • Air Inlet
    • Air Outlet
  3. Select Create One Region for All Parts and enter Solid Components in the neighboring text box.
  4. Click Apply then Close.
    Simcenter STAR-CCM+ creates the region, Solid Components.
  5. Expand the Interfaces node.
  6. Rename the interfaces as follows:
    Old Name New Name
    Air Case/Air Inlet Case Fans
    Air Case/Capacitor 1 Air/Solid Components
    Capacitor 1/PCB Solid Components/Solid Components
  7. Save the simulation.