View factor

In radiative heat transfer, a view factor, ${\displaystyle F_{A\rightarrow B}}$, is the proportion of the radiation which leaves surface ${\displaystyle A}$ that strikes surface ${\displaystyle B}$.

In a complex 'scene' there can be any number of different objects, which can be divided in turn into even more surfaces and surface segments.

View factors are also sometimes known as configuration factors, form factors or shape factors.

Because radiation leaving a surface is conserved, the sum of all view factors from a given surface, ${\displaystyle S_{i}}$, is unity:

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