Opera 2D

Hi. I dont know whether I have posted regarding this or not. Because the internet was a but slow so I had to refresh. I search for the post but it's not there so I'm gonna try posting again just in case.

I am suppose to use the software OPERA 2D to analyze the electric field distribution. my model consist of a solid insulator sandwiched between two electrodes. The upper electrode is at potential 20kV and the bottom one is grounded. The insulator has a void in the middle which is the reason for this analysis.

The solid insulator material is rubber/porcelain with relative permittivity of 5.2, but the problem is I don't know what material label to assign and which bh curve to use to define the material. Theoretically, I know how the electric field contour suppose to show, but to model it and prove it using this software is confusing.

I have searched online through forums and websites but to no avail. So, I really hope someone can help me out here.

Thank you :)