Hello, I am implementing a terrain model with some conducting ground (soil) by means of a material_function, which is an interpolation function of values (height over distance) that I load from a .csv file (this is similar to the ring_resonator example function in the tutorials), with a curvature of the material_function being in the range of the resolution (250).
I set the material as mp.Medium(epsilon=10, D_conductivity=37), where D_conductivity should correspond to an E-conductivity of σ = 0.001 S/m in my simulation. This material gets returned by the material_fct and the corresponding geometry is a block: mp.Block(mp.Vector3(1e20,1e20,ground_thickness), center=mp.Vector3(0,0,geom_center_point), material=material_fct) My simulation is cylindrical and the resolution is 250, simulation cell being 120x14 (yes this takes long :-) When I perform the simulation, the fields bounce around quite a lot the farther away I read out the field (from distance >10 on), which appears to be too extreme to me (almost unstable, but not fully, just large amplitude swings). Strange thing is, that when I simulate the same terrain with a mp.perfect_electric_conductor instead, the fields behave normally. What could be the reason? 1) Is the curvature of my terrain maybe too strong for the higher frequency components of the transient pulse to be still stable (in other words, is my resolution still too coarse for the small wavelength components)? 2) If I activate the subpixel averaging by material_fct.do_averaging = True, it doesn't get better. Maybe because σ is not smoothed (as mentioned in the docs) and contributes to the artifacts more than the epsilon? Thank you for any help! Best, Hannes
pEpkey.asc
Description: application/pgp-keys
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