I'm new to Elmer software that I downloaded two days ago.
I wanted to start with a very simple case: Compute the transient temperature profile through an homogeneous material in response to a power transient applied through the upper surface.
Conditions are straightforward: Constant temperature on the bottom surface, perfectly insulated side surfaces, power transient applied through upper surface. Body to simulate is 1mmx1mmx0.28mm.
First issue: I used FreeCAD to design this simple shape and imported into Elmer. No issue to import and mesh it, but units have been lost in the process, so my shape was imported as a 1mx1mx0.28m which obviously increases by 1.0e6 the transient thermal response time. Any way to restore the original geometry? FreeCAD will not let me input a dimension of 0.001m, will replace it by 1mm.
Second issue: I struggled to insert the input heat flux condition through the upper surface. I thought first that units should be W/m² as it is defined as an heat flux through a 2D boundary. I realized digging into the model documentation that Elmer expects a mass heat generation in W/kg. How should I convert my input transient surface flux in W/mm² into the unit expected by Elmer? I can convert to W/m² easily, but dividing by material density in kg/m3 is nonsense as it would lead to W/kg*m.
I hope some of the experienced users on this forum will be able to help.