Steady State Thermal Analysis Winter Semester

2 Goals  In this workshop we will analyze the pump housing shown below for its heat transfer characteristics.  Specifically a plastic and an aluminum version of the housing will be analyzed using the same boundary conditions.  Our goal is to compare the exposed surface temperatures for each configuration and to investigate the distribution of heat flux in the part.

3 Assumptions Assumptions:  The pump housing is mounted to a pump which is held at a constant 60 deg. C. We assume the mating face on the pump is also held at this temperature.  The interior surfaces of the pump are held at a constant temperature of 90 deg. C by the fluid.  The exterior surfaces are modeled using a simplified convection correlation for stagnant air at 20 deg. C.

4 Start Page  From the launcher start Simulation.  Choose “Geometry > From File... “ and browse to the file “Pump_housing.x_t”.

5 Preprocessing  Change the part material to “Polyethylene”: 1.Highlight “Part1” 2.In the Detail window “Material” field “Import...” 3.“Choose” material “Polyethylene”. Set the working units to (m, kg, N, C, s, V, A) “Units” menu choose

6 Steady State Thermal Analysis  Insert new thermal analysis for steady state conditions: “New Analysis”  “Steady state thermal”

7  Highlight the “Steady state thermal” branch. Select the interior (13) surfaces of the pump housing (hint: use Extend to limits feature).  Under “Environment” menu, add “temperature” and set its magnitude to 90 degree C Environment

8  Select the mating surface (1) of the pump housing.  Under “Environment” menu, add “temperature” and set its magnitude to 60 degree C. Environment

9  Select the exterior (41) surfaces of the pump housing (hint: use extend to limits feature).  Under “Environment” menu, add ”Convection”

10 Environment  In the details window, change the film coefficient to temperature depended by choosing “Tabular (temperature)”.

11 Environment  “Import” the correlation “Stagnant Air – Simplified Case”.  Set the “Ambient Temperature” field to 20 deg. C.

12 Solution  Add temperature and total heat flux results. Highlight the Solution branch. “RMB > Insert > Thermal > Temperature”  Repeat the above steps to add “Total Heat Flux”.

13 Duplicate Model  Before solving we will duplicate the model and specify a different material for the pump housing. This will allow us to compare the responses for each.  Highlight the “Model” branch.  “RMB > Duplicate”.  From the new branch “Model2” highlight “Part1”  In the detail window “Import” the material “Aluminum Alloy”.

14 Solution  Highlight the “Project” branch in the tree and solve.  Note: by issuing a solve from the Project branch both Model branches will be solved. If single solutions are desired highlight only the branch to be solved before beginning the solve.

15 Postprocessing  When the solutions are complete, inspect the temperature plots and compare. It can be seen quickly that the choice of material in this case has a significant effect. Aluminum Polyethylene

16 Postprocessing  A similar comparison of the heat flux in each model points up differences. Here a vector heat flux plot is shown in wireframe mode. Note how much of the energy in the aluminum model is returned via the mating face. Aluminum Polyethylene

17 Postprocessing Generating the heat flux vector:  Highlight the "Total heat flux" under the "Solution" branch.  Select the Graphic view in the results menu.  The following menu will be shown up:  Note that you can change the arrows density, type, etc.

18 Postprocessing  To better view the exterior surface temperatures we will employ scoping as in previous workshops.  Select the outside (41) surfaces of the pump housing (use extend to limits).  “RMB > Insert > Thermal > Temperature” (note the scope of the new result now indicates “41 Faces” rather than “All Bodies”  Using RMB, copy/paste the new result into Model 2 Solution branch. Notice the scope of the result remains in tact.  Solve from the Project branch.

19 Postprocessing  The 2 new plots now display outside temperatures for both models. Notice the contours are not affected by interior temperatures as were the previous plots. Aluminum Polyethylene

20 Reporting  If time permits, create figures to include in a report and generate the report.