What is the highest efficiency (electromagnetic) radiator shape?
That makes no sense to me.No, I mean an engine radiator, emitting infrared at about 250 Kelvin
I'm talking about a radiator that exchanges heat only by thermal radiation - no convection or heat conduction *out* from it. Somewhat similar to a spacecraft radiator, but without constraints on weight and portability. I should also add that a single flat surface is not what im after, even though it's probably the most radiative per volume.That makes no sense to me.
Please help us to help you.
Do you mean like the radiator in the front of your car? Or radiators on spacecraft to shed excess heat? Please don't keep us guessing. Can you use Google Images to find an image of the kinds of "radiators" that you are asking about?