Hello All,
I am modelling a geometry of two concentric cylinders (made of different materials) with a vacuum between the two cylinders in Comsol Multiphysics. I've been able to setup the geometry by creating three concentric cylinders and using a 'difference' to extract the middle cylinder. By doing this, my assumption was that this would lead to vacuum properties in the intermediate region when conducting my radiation diffuse surface simulations.
I searched through the materials library and vacuum is not an option, so I assumed that this is the most effective way to do this. However, the produced results were rather unexpected.
Please let me know if what I am doing here seems correct or if there is something that I've failed to understand and missed along the way.