Note that displaying the plot in log scale can be very useful for this purpose. You can see that the fields extend all the way through PML. Therefore, you can see if the fields are zero at the end of PML.Īs an example, we have setup an incorrect simulation where the modes are artificially confined by PML. The modal field profiles shown in the mode plot include the PML region.
#Fdtd pml how to
Question 2: How to know if the PML is not completely absorbing? The reason is that alpha is a stability factor that is not used in FDE since it is frequency domain solver. 3, 2010Īdditionally, you might notice that compared to FDTD, the parameter alpha is not available in FDE. Zhao, An Auxiliary Differential Equation Formulation for the Complex-Frequency Shifted PML, IEEE Trans. On contrary, making kappa too large could cause that perfectly matched layer is not matched anymore.įor detailed understanding of the PML model and the related parameters, you can read the following paper that describes the detailed meaning of each parameter and the PML concept as a whole: S.
Sigma is exaggerated by default(sigma=5) in FDE and kappa is related to spatial distribution of PML and the default settings kappa=1 should be usually a good option for your simulations.
In particular, we focus on aspects of implementing a full-fea.
#Fdtd pml free
You should not need to adjust the parameters kappa and sigma. FDTD Maxwellsolver This paper describes Meep, a popular free implementation of the nite-difference time-domain (FDTD) method for simulating electromagnetism. If you find that the PML is not being completely absorbing, for examplewhen the incident light and the field is non-zero when it reaches the end of PML, then you can increase the number of layers.
0 kommentar(er)
