Field cage simulation

Hi,


I am simulating a 300 V/cm electric field generated by a field cage composed of square copper plate (see enclosed figure). The mother volume is just a box of air, but in reality a gas will be used. I would like to include delrin rods to support the rings, kapton on the chamber wall as non conductive material to avoid breakdown voltage and finally for the wall it-self aluminium. Can I belive COMSOL results if I include these materials ? Can COMSOL simulate the charge accumulation ? and if yes what should I do to include it ?

Thanks in advance, sincerely,

Igal.