Frequency domain TLM applied to microwave heating

The frequency-domain TLM method (TLM-FD) is used to find power distributions in dielectric loads inside multimode cavities. Results for the original TLM-FD node with all line impedances equal are compared to results for the same problem with the newer `distributed´ node that has all line phase constants equal. It is shown that the original node produces unacceptable errors on a problem with a graded mesh. Iterative techniques for use with TLM-FD are discussed and a study is made of the convergence of a problem when the permittivity is changed in steps, as would occur during the simulation of heating of a material with temperature dependent dielectric properties. A comparison is made of the run-time and storage requirements of a time-domain and frequency-domain TLM simulations