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JoeAltmaier • yesterday at 9:32 PM • 2 replies • view on HN

Surface area is a materials problem? Folded microstructure, atomic-scale textured surface or some other science-fiction solution could have square kilometers of surface area in a shoebox.


Replies

AlotOfReading • yesterday at 10:40 PM

Imagine you have two blackbody radiators with the same bulk properties, except one has surface area shenanigans like aerogels. In the far field as a whole, it seems like both should radiate essentially the same regardless of the internal details. You can shape emissive direction, or improve efficiency of non-ideal materials, but even ideal materials don't fix the issues pointed out by the parent.

sgsjchs • yesterday at 10:38 PM

It needs to be facing open space instead of other parts of itself, otherwise the radiation is just reabsorbed.