Create duct boundary conditions in a thermal model

Practice defining duct boundary conditions in a thermal model. You will specify immersed ducts boundaries and solve a transient solution, using a mold cooling model.

Download and extract the part files.

Open the Simulation file

Open the Simulation file and reset the dialog box settings.

  1. Choose File→Open and open mold_cooling\drone_mold_sim.sim.
  2. Choose File→Preferences→User Interface and on the Dialog and Precision page, reset the dialog box memory.

Define duct flow boundary conditions

Define inlet and outlet boundary conditions on the ducts.

  1. Choose Home tab→Loads and Conditions group→Simulation Object Type list→Duct Flow Boundary Conditions .
  2. On the Top Border bar, from the Type Filter list, select Element.
  3. In the graphics window, select the displayed element.
  4. In the Parameters group, from the Mode list, select Mass Flow.
  5. In the Mass Flow (per Element) box, type 0.01 kg/s.
  6. Click Apply.
  7. From the type list, select Duct Opening.
  8. On the Top Border bar, from the Type Filter list, select Node.
  9. In the graphics window, select the displayed node at the bottom of the duct.
  10. In the External Conditions group, from the External Temperature list, select Specify.
  11. In the Temperature Value box, type 20 °C.
  12. Click Apply.
  13. In the graphics window, select the displayed node on the other end of the duct.
  14. Click OK.

Define immersed duct boundary condition

Define an immersed ducts boundary condition and specify an expression for the heat transfer coefficient.

  1. Choose Home tab→Loads and Conditions group→Simulation Object Type list→Immersed Ducts .
  2. On the Top Border bar, from the Type Filter list, select Mesh.
  3. In the graphics window, select the three displayed meshes representing the ducts.
  4. In the Magnitude group, in the Heat Transfer Coefficient box, type 2*HTCFORCE( 2.5,"DUCT_FULL") W/(mm2·°C).
    HTCFORCE returns the heat transfer coefficient. DUCT_FULL models the convective heat transfer between the fluid in the duct network, with fully developed flow, and the walls of the duct.
  5. Click OK.

Solve the model

  1. In the Simulation Navigator, right-click the Solution 1 node and choose Solve.
  2. Click OK.
  3. Wait for the solve to end, before proceeding.
  4. In the Review Results dialog box, click No.
  5. Close the Information window.
  6. In the Analysis Job Monitor dialog box, click Cancel.

Post process the results

  1. In the Simulation Navigator, expand the Solution 1→Results nodes and double-click the Thermal node.
  2. In the Post Processing Navigator, expand the Thermal→Increment 11, 10.00s nodes, and double-click the Temperature - Elemental node.
  3. Choose Results tab→Animation group→Animate .
  4. From the Animate list, select Iterations.
  5. Click Play to show how the temperature varies during iterations, and click Stop .
  6. Click Close.
  7. Expand the Post View 1 → Mesh Collectors nodes and hide drone_mold_fem.fem to hide the corresponding meshes.
  8. Show Annotations to display the maximum and minimum temperature values calculated on the shell elements.
  9. In the Simulation Navigator, right-click the Solution 1 node, and choose Browse to open the solution directory.
  10. Open the drone_mold_sim-Solution_1.GroupReport.htm file to explore the temperature values in each time step.
    The solver generates this temperature report over the mold as requested in the drone_report simulation object.
  11. Compare the mold's maximum and minimum temperature values from the report with those displayed in the graphics window.
  12. In the Post Processing Navigator, expand the Post View 1→Groups nodes and double-click the Immersed Ducts(1)-Elemental node to identify if the immersed ducts and solid elements are correctly thermally connected.
You have completed this lab.