Shielding at power frequency using femlab

[sanshyme]

Hi

I am doing shielding at power frequency using femlab. i have done 2D modeling on a room using reinforcement bars instead of a full shield and i wonder why is the bar inclined at 45 degrees will give a better shielding effeciency than at 90 degree?

in the real world, when do we use multiple reinforcement bars instead of a full shield in a room?

thanks
serene

 

[berkeman]

Must be some quirk of the simulation program. Does it let you plot shielding effectiveness as a function of the radiation's angle? It sounds like your shielding simulation for "power frequency" is for 50-60Hz, right? That's not typically what I've seen shielded rooms used for. The shielded rooms and anechoic chambers that I've been in are for EMI and other RF testing work. The frequency range of interest where the room has to have very good shielding integrity is typically from a few 100kHz up through a few GHz. You only get that with a full shield room, including conductive gasketing on all openings like doors and cable feed-through ports.