Questions / Feedback

[solarjoe]

Hello, I came across Energy2D while looking for a software to estimate a simple heat transfer problem. Usually I use Elmer for that kind of calculations. A few years ago I used Algor, now known as Autodesk Simulation.

I am working as consulting engineer and we often have to make quick estimations where a steady-state node model is to simplified and setting up a complex FEM model is overkill.

Energy2D is a very handy tool for something that and I like the click'n'play sandbox feeling in combination with the physical correctness. I never thought FEM could be that fun :)

I also have a few remarks and questions:

• My simple case simulates the cooling of a hot metal plate, conduction to ground, convection in air above it. So far the boundaries of the grid act like walls and lid and eddies form in the corners of the grid. But I would like the hot air to be able to "leave the grid", especially above the plate. I played with the thermal and mass boudary conditions, but could not find a way to achieve this.

  • Can you tell me how to do this?
  • Does the mass boundary only relate to particles or is this also for convective air?

• Which physical properties are affected by "reference temperature" and "temperature coefficient"?

• Just out of interest: How do you handle the case when the same space in the grid is occupied by two bodies, e.g. overlapping rectangles?

• I saw what people often ask about the time step size. You could mention the Courant number as indicator for that. http://inside.mines.edu/~epoeter/583/13/discussion/courant.htm https://en.wikipedia.org/wiki/Courant%E2%80%93Friedrichs%E2%80%93Lewy_condition

• I could not find a Wikipedia entry for Energy2D. There really should be one And it should be mentioned in https://en.wikipedia.org/wiki/List_of_finite_element_software_packages

• I could not find a link to the github page on your homepage.

[charxie]

Hi solarjoe, I wish I had seen your post earlier. But I didn't come to check here often. Is it too late if I respond to your questions now?

[solarjoe]

Yes, I am still interested in the answers. I am not using it at the moment, but will for sure in the future.

[wookey]

Solarjoe. Wikipedia is a wiki - you can just add stuff yourself :-) I've just done it, so energy2D is now on that (very handy) page.