Queries, comments, suggestions? Please contact us.



Area Lighting / Lighting technology and daylighting

IEV ref 845-29-094

Symbol
f12
f21

en
form factor, <between two surfaces>
quotient of the average radiant flux density or luminous flux density, Φ2/A2 (or Φ1/A1), received over surface S2 (or S1) from surface S1 (or S2) and the radiant exitance or luminous exitance, M1 (or M2), of surface S1 (or S2)

f 21 = Φ 2 A 2 M 1 = g A 2 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadAgadaWgaaWcbaGaaGOmaiaaigdaaeqaaOGaeyypa0ZaaSaaaeaa cqqHMoGrdaWgaaWcbaGaaGOmaaqabaaakeaacaWGbbWaaSbaaSqaai aaikdaaeqaaOGaamytamaaBaaaleaacaaIXaaabeaaaaGccqGH9aqp daWcaaqaaiaadEgaaeaacaWGbbWaaSbaaSqaaiaaikdaaeqaaaaaaa a@445F@

or

f 12 = Φ 1 A 1 M 2 = g A 1 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadAgadaWgaaWcbaGaaGymaiaaikdaaeqaaOGaeyypa0ZaaSaaaeaa cqqHMoGrdaWgaaWcbaGaaGymaaqabaaakeaacaWGbbWaaSbaaSqaai aaigdaaeqaaOGaamytamaaBaaaleaacaaIYaaabeaaaaGccqGH9aqp daWcaaqaaiaadEgaaeaacaWGbbWaaSbaaSqaaiaaigdaaeqaaaaaaa a@445D@

with

A 2 f 21 =g= A 1 f 12 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadgeadaWgaaWcbaGaaGOmaaqabaGccaWGMbWaaSbaaSqaaiaaikda caaIXaaabeaakiabg2da9iaadEgacqGH9aqpcaWGbbWaaSbaaSqaai aaigdaaeqaaOGaamOzamaaBaaaleaacaaIXaGaaGOmaaqabaaaaa@42A7@

where Φ2 (or Φ1) is the radiant flux or luminous flux received over surface S2 (or S1) from surface S1 (or S2), A2 (or A1) is the area of surface S2 (or S1) and g is the mutual exchange coefficient

Note 1 to entry: The form factor has unit one.

Note 2 to entry: This entry was numbered 845-09-73 in IEC 60050-845:1987.


fr
facteur de forme, <entre deux surfaces> m
quotient du flux énergétique ou lumineux surfacique moyen Φ2/A2 (ou Φ1/A1), reçu par la surface S2 (ou S1) en provenance de la surface S1 (ou S2) par l'exitance énergétique ou lumineuse, M1 (ou M2), de la surface S1 (ou S2)

f 21 = Φ 2 A 2 M 1 = g A 2 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadAgadaWgaaWcbaGaaGOmaiaaigdaaeqaaOGaeyypa0ZaaSaaaeaa cqqHMoGrdaWgaaWcbaGaaGOmaaqabaaakeaacaWGbbWaaSbaaSqaai aaikdaaeqaaOGaamytamaaBaaaleaacaaIXaaabeaaaaGccqGH9aqp daWcaaqaaiaadEgaaeaacaWGbbWaaSbaaSqaaiaaikdaaeqaaaaaaa a@445F@

ou

f 12 = Φ 1 A 1 M 2 = g A 1 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadAgadaWgaaWcbaGaaGymaiaaikdaaeqaaOGaeyypa0ZaaSaaaeaa cqqHMoGrdaWgaaWcbaGaaGymaaqabaaakeaacaWGbbWaaSbaaSqaai aaigdaaeqaaOGaamytamaaBaaaleaacaaIYaaabeaaaaGccqGH9aqp daWcaaqaaiaadEgaaeaacaWGbbWaaSbaaSqaaiaaigdaaeqaaaaaaa a@445D@

avec

A 2 f 21 =g= A 1 f 12 MathType@MTEF@5@5@+= feaagKart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHX garuavP1wzZbItLDhis9wBH5garmWu51MyVXgaruWqVvNCPvMCG4uz 3bqee0evGueE0jxyaibaieYdi9WrpeeC0lXdh9vqqj=hEeea0xXdbb a9frFj0=OqFfea0dXdd9vqaq=JfrVkFHe9pgea0dXdar=Jb9hs0dXd bPYxe9vr0=vr0=vqpWqaaeaaciWacmGadaGadeaaeaGaauaaaOqaai aadgeadaWgaaWcbaGaaGOmaaqabaGccaWGMbWaaSbaaSqaaiaaikda caaIXaaabeaakiabg2da9iaadEgacqGH9aqpcaWGbbWaaSbaaSqaai aaigdaaeqaaOGaamOzamaaBaaaleaacaaIXaGaaGOmaaqabaaaaa@42A7@

Φ2 (ou Φ1) est le flux énergétique ou lumineux reçu par la surface S2 (ou S1) en provenance de la surface S1 (ou S2), A2 (ou A1) est l'aire de la surface S2 (ou S1) et g est le coefficient d'échange mutuel

Note 1 à l'article: L'unité de facteur de forme est un.

Note 2 à l'article: Cet article était numéroté 845-09-73 dans l'IEC 60050-845:1987.


ar
عامل الشكل, <بين سطحين>

de
Formfaktor, <zwischen zwei Flächen> m

it
fattore di forma, <tra due superfici S1 e S2>

ko
형태 계수, <두 표면 S1 과 S2 사이>

ja
形態係数
固有入射光束係数

pl
współczynnik kształtu, <między dwiema powierzchniami> m

pt
fator de forma, <entre duas superfícies S1 e S2>

zh
形状系数, <两表面S1和S2间的>

Publication date: 2020-12
Copyright © IEC 2021. All Rights Reserved.