BlueEyes Technology
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12. Emissivity
Emissivity is a measure of the relative strength of the energy released by the surface of an object in the
form of thermal radiation. The emissivity of an object is equal to the ratio of the energy emitted by the
object at a certain temperature to the energy of blackbody radiation at the same temperature. The
emissivity of a black body is equal to 1, and the emissivity of other objects is between 0 and 1. Emission
rate is a pure quantity. In general, the darker the color of the material or the rougher the surface, the
closer the emissivity will be to 1.
The following is a reference for the emissivity of various materials.
Material.
Emissivity
Material.
Emissivity
Material.
Emissivity
Human Skin
0.95-0.98
soils
0.93
polycarbonate
0.8
concrete
0.97
PVC plastic
0.93
Copper oxide
0.78
water
0.96
lacquer
0.9
brick
0.75
Tapes
0.96
black paper
0.86
gypsum
0.75
asphalt
0.96
wood
0.85
Stainless Steel
0.14
Black Aluminum
0.95
Cast iron
0.81
aluminum plate 0.09
rubber
0.95
rust
0.8
copper plate
0.06
