Altair RISE

A program to recognize and reward our most engaged community members

Nominate Yourself Now!

Medium of a polygon in Feko

I have a simple doubt. I have a 2D polygon (XY plane) on my model and the incident plane wave and electric field is also on the same plane (XY plane) and the magnetic field is perpendicular to the plane XY (on z). Theoretically the monostatic RCS should be the same for a PEC and for a Free space medium inside the polygon as the wave can't penetrate inside. And, unfortunately I can't change the properties of the edges. Edges remains edges. I can't put any material for edges in the model. And, I get different results for a PEC and for a Free Space medium inside the polygon. Why? I have made a comparison on PEC and free space. Please help.

Unable to find an attachment - read this blog

Find more posts tagged with

English

Feko

Accepted answers

All comments

Mel

Hi Lostarmour

You attached a *.eps file. Please attach the cfx.

lostarmour

Hi Lostarmour

You attached a *.eps file. Please attach the cfx.

Hi Mel,

This is the cfx file. Here the medium inside the surface of the polygon is PEC. So, if you see my plane wave model of incidence, it should be the same if I fill the medium with free space. However, I have different results. Is Feko treating the PEC as a finite conductance such that causes some kind of current distribution on the surface even though the electric field is just on the plane of the surface? Or does it consider the PEC to be of infinity conductivity?

EDIT:

I have attached the free space model too.

Unable to find an attachment - read this blog

Mel

Please also attach the model where you defined 'Free space'.

lostarmour

Please also attach the model where you defined 'Free space'.

I have attached both. The second figure is wires and inside is Free Space.

Mel

PEC is treated as infinite conductivity.

The 'gaps' inside the wire model is of the order of the wavelength so I would not say these models are equivalent.