2 A Workflow Combining Ansys Sherlock, Icepak, and Mechanical to Evaluate the Reliability of Electronic Systems
Figure 2: Sherlock Model Export Interface.
2. Once you have built a PCBA in Sherlock, it can be exported directly into Workbench. Sherlock automates a variety of functions to
facilitate the creation of a functional FEA model, including part size filtering, enabling/disabling of component leads, body facet-
ing for easy meshing, and creation and assignment of material properties.
3. With a model of the PCBA now in Workbench, you are free to make changes to the geometry, such as adding housings or other
structural details. It is sometimes advisable to create a copy of the model, so that different versions of the model can be used in
Icepak and Mechanical. Sometimes, because the meshing and solving is done differently in CFD vs. FEA, it is preferable to have
minor geometric differences depending on which tool is being used.
4. In this analysis, we use Ansys Electronics Desktop (AEDT) to conduct two Icepak/HFSS iterative PCBA temperature analyses:
• Natural Convection only.
• Forced convection with three 3.0 CFM fans.
Power dissipations are applied on several critical components and 20˚C ambient air within the larger box is assumed.
5. Icepak is used to calculate temperature gradients throughout the PCBA; however, it does not account for power losses inside the
PCB, which can sometimes result in significant temperature rises. The Ansys HFSS 3D layout tool is used to calculate tempera-
ture dependent losses inside the PCB.
Figure 3: Workbench View of the Exported Model.
Figure 4: PCBA Geometry from Sherlock (top left) and PCBA after Housing is added in Spaceclaim.
