I have an evaluation copy of Hyperlynx Thermal that I want to accurately model a multilayer board design with lots of thermal vias and plane layers.
So I started with a very basic 2 layer board, and put down a 2W surface mount component with isloated copper pours on the top and bottom side. I ran the anaylsis, then added a few thermal vias to connect the two copper pours through the board underneath the device. No change in component temperature with the added vias. Obviously HT is not using the via information from my layout tool (PADS v9.4), very disappointing.
So I then used the "Thermal Via" tool in Hyperlinx to manually add the vias underneath the component. Now my component is HOTTER than before, which is physcially impossible!
What's going on here? How do I accurately model thermal vias in Hyperlynx? Or do I need to use 3D solver such as FloTherm?