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configuration factor, <between two surfaces>

c21; c12

quotient of the irradiance or illuminance, E2 (or E1), at a point on surface S2 (or S1) due to the flux received from surface S1 (or S2) and the radiant exitance or luminous exitance, M1 (or M2), of surface S1 (or S2)


Note 1 to entry: The relation between the configuration factor, c, and the (mutual) exchange coefficient, g, is:

where Φ2 (or Φ1) is the flux received over surface S2 (or S1) from surface S1 (or S2) and A2 (or A1) is the area of surface S2 (or S1)

Note 2 to entry: The configuration factor has unit one.

Note 3 to entry: This entry was numbered 845-09-72 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-246 in CIE S 017:2011.

Publication date: 2020-12
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