The subject of this paper is the thermal simulation of the printed circuit boards. After the theoretical review I will introduce the simulation models used previously. My main goal was to create a model that take into consideration the material inhomogeneity, which is using variable density meshing, so I can observe the effects of the board’s copper drawing.
First, I learned the basics of simulation, I get acquainted with the serious mathematical background behind the modeling. My job was carried out in MATLAB environment. I created a simulation program, that I wrote from the basic level of theoretical considerations. Although this model is two-dimensional and uses a number of simplifications, nevertheless, it was an important step, as it has helped me to show the right way of moving forward. The changing of the parameters under the simulation was followed by the results that meet the the requirements of the real world.
Considering the advantages of MATLAB, I modified the 2D model. From step by step I increased the accuracy, from 2D homogeneous case to 3D homogeneous, then to the final inhomogeneous version. After I managed to solve the emerging problems, I created a close to reality PCB structure, which was observing the effect of the thermal copper wiring. Two types of boundary conditions were examined: the effect of heating parts, as well as the reflow oven. The results of the simulations were that the wiring has a serious effect near by the heating chip, it greatly helps its heat dissipation. Furthermore, it became observable that the copper’s temperature rise much faster in reflow environment than the FR4’s.