Imprint is a CAD operation that helps to recognize solid/solid and solid/fluid interfaces. Later on, these interfaces will be assigned as contacts in Conjugate Heat Transfer (CHT) or Finite Element Analysis. The contact definition is vital since these regions are responsible for transferring heat and loads between parts.
Before going through the effect of imprinting a geometry, let’s first see how to perform this operation in SimScale. The imprint operation can be run within the CAD mode environment:
In CAD mode, the user will be able to directly create and run an Imprint operation, as in Figure 2:
After running the operation, you can click on Finish on the top-right corner to export the updated CAD model to the Workbench.
Now that we know where to imprint a model, let’s see what it does to the geometry. The following picture represents an assembly, which consists of two solid parts that touch.
Without an imprint operation, the interface between the solid bodies may not be correctly recognized and grouped as partial interfaces. This will be the case, for example, if we have an enclosure enveloping the two parts.
In this case, the highlighted face (red) shares contact with both an air domain and a solid body. To prevent partial contact, the face should be split into two interfaces, one between the solid part, and the other between the air domain.
The imprint operation does exactly that – it splits the surfaces so that we can have precise contact detection. Comparing the highlighted face from Figure 3, we can see that it now has been split in two, due to the imprint operation:
In this case, we can obtain valid contacts in the simulation setup.