Results for: emissivity

Why heat sinks are black anodized?

Radiative heat transfer (heat transfer by electromagnetic radiation) is proportional to e*(T1^4 - T2^4) where T1 is the absolute temperature of the material, T2 is the absolute temperature of the surroundings, and e is the emissivity coefficient. A black material… Full Answer

What is normal spectral emissivity?

Normal is equal to vertical.Flat object radiates light and heat to hemisphere space.Sometimes,it is convenient to measure the vertical direction.Hemisphere spectral emissivity ε and normal spectral emissivity rate εn have a relationship: ε =Mεn, M is correction factor. Full Answer