Unofficial
FEMM
documentation
by Dr Stan Zurek

This tutorial shows a very simple problem for HEAT FLOW coupled with MAGNETIC simulation.

Open FEMM and start new problem, menu > File > New .

Select Magnetics problem from the pop-up window, and set up magnetic problem as shown in Fig. 1 (example file can be downloaded at the bottom of this page). In this example there is single copper conductor next to a single magnetic block, both surrounded by a layer of non-magnetic (lossless) resin, and all of the geometry is placed in air.

Fig. 1. Magnetic problem

Once the magnetic problem is solved it is necessary to extract the power loss data from the regions of interest. Fig. 2 shows the sequence in which a given region can be selected, and the integral for Total Loss Density in W/m^3 can be extracted. This value will be used for the corresponding region in the Heat/Thermal model.

The values of loss density should be extracted for each region which contributes to power loss.

But all the lossless regions (such as air) will have zero loss by definition, so there is no need to process them.

In this example there are just two regions with loss:

• Copper bar = 706971 Watts/meter^3
• Magnetic bar = 77860.5 Watts/meter^3

Fig. 2. Use magnetic solution