For simulations involving conjugate heat transfer (CHT) analysis, the requirements for the simulation domain are slightly different from the normal procedure where we create a flow volume covering the negative of our overflowed geometry which represents the physical walls. This article describes how to proceed with CHT simulations ensuring the flow domain is accurately created.
A) Create Flow Volume and Keep Existing Parts
CHT simulation involves heat transfer through both solids and fluid. Hence, we need to keep the original solid parts while extracting the fluid volume as they participate in the heat transfer too. Accordingly, when we create the flow volume we need to keep the existing parts.
As an example, the following image shows the case of an electronics box:
In order to understand the difference, the following picture shows both the results for a flow volume extracted with (right) and without keeping the existing parts (left):
This is only necessary if you have a CHT simulation (or when you want to see the heat transfer through the walls/solids). In any other simulation you will get the same results, whether you keep the existing parts or not.
B) Imprint the Geometry
In order to know where the physical contacts between two solids are, we need to perform an imprint. This action basically cuts the interface between two bodies in physical contact into recognizable surfaces. Please refer to our article where a detailed explanation of what an imprint does is well mentioned.
As a result, when we create the CHT simulation, the tool detects the interfaces automatically. If you need to, you can further change the thermal properties of the interfaces.
If the above example caught your interest, quickly jump to the Thermal Management: CHT Analysis of an Electronics Box tutorial where you will learn to visually inspect and manage the temperature distribution inside an electronics box.