Reflectivity of a black body is zero.The following is a list of the common terms used in the context of radiation heat transfer and their definitions.
Ideal radiator, emits and absorbs the maximum possible amount of radiation at any temperature and wavelength. An example of a blackbody is a small opening in a heated cavity.
Rate at which radiation is incident on a surface from all directions per unit area.
Rate at which radiation leaves a surface due to emission and reflection in all directions per unit area of the surface.
Fraction of incident radiation absorbed by the surface.
Fraction of incident radiation reflected by the surface.
Reflectivity of a black body is zero.
Fraction of incident radiation transmitted by the surface.
The software assumes that the transmissivity
is zero.
The following relation relates absorptivity, reflectivity, and transmissivity of a surface: a + r + t = 1.
Rate of radiation emitted by a surface in all directions per unit area of the surface. The unit of E is W/m2.
Ratio of the emissive power of a surface to the emissive power of a blackbody at the same temperature.
e = E/Eb
where Eb is the emissive power of a blackbody at the same temperature. The emissivity of a surface is a function of temperature.
Radiation Emission from Real Surfaces
Radiation Exchange Between Surfaces