>>12428779heat transfer can be summarized to the following causes: by conduction, flow and radiation.
conduction: happens without any movement.
flow: superimposes the heat transport by conduction. the flow can be natural or forced(with a pump or compressor,..).
radiation: emission or absorption of electromagnetic radiation.
>If air is such a good insulator, how come our bodies rapidly change in temperature being exposed to it?mainly because flow but also because of moisture emission from skin. water that evaporates at 37.5°C also requires a heat source.
the human sense of warmth also responds to radiation. see radiator or campfire. missing heat radiation is also perceived as cold sometimes.
or opposite, see sunny beach.
>and what would be a perfect insulation then?best is vacuum and as less radiation as possible. the radiation of bodies can be optimized by coating, see inside of an insulating can.
>and what is the average solution?use material with low conductivity and prevent flow as much as possible. so, porous material with gas inside and only thin walls around.
small pores make it difficult for the gas to circulate. so you force the gas to stand still as best you can.
the material of the wall should also have a small heat conductivity of course.
there are also vacuum plates to buy, with porous material without any gas inside and an outer film.
