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Area Lighting / Lighting technology, day lighting

IEV ref845-09-73

Symbol
f

en
form factor (between two surfaces S1 and S2)
ratio of the average radiant or luminous flux density received over surface S2 (or S1) from surface S1 (or S2) to the radiant or luminous exitance of surface S1 (or S2)

f 21 = Φ 2 A 2 M 1 = g A 2 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaWgaaWcbaGaaGOmaiaaigdaaeqaaOGaeyypa0ZaaSaaaeaacqqHMoGrdaWgaaWcbaGaaGOmaaqabaaakeaacaWGbbWaaSbaaSqaaiaaikdaaeqaaOGaamytamaaBaaaleaacaaIXaaabeaaaaGccqGH9aqpdaWcaaqaaiaadEgaaeaacaWGbbWaaSbaaSqaaiaaikdaaeqaaaaaaaa@4295@ ; A 2 f 21 =g= A 1 f 12 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadgeadaWgaaWcbaGaaGOmaaqabaGccaWGMbWaaSbaaSqaaiaaikdacaaIXaaabeaakiabg2da9iaadEgacqGH9aqpcaWGbbWaaSbaaSqaaiaaigdaaeqaaOGaamOzamaaBaaaleaacaaIXaGaaGOmaaqabaaaaa@40DD@

unit : 1


fr
facteur de forme (entre deux surfaces S1 et S2) m
rapport du flux énergétique ou lumineux surfacique moyen reçu par la surface S2 (ou S1) en provenance de la surface S1 (ou S2), à l'exitance énergétique ou lumineuse de la surface S1 (ou S2)

f 21 = Φ 2 A 2 M 1 = g A 2 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadAgadaWgaaWcbaGaaGOmaiaaigdaaeqaaOGaeyypa0ZaaSaaaeaacqqHMoGrdaWgaaWcbaGaaGOmaaqabaaakeaacaWGbbWaaSbaaSqaaiaaikdaaeqaaOGaamytamaaBaaaleaacaaIXaaabeaaaaGccqGH9aqpdaWcaaqaaiaadEgaaeaacaWGbbWaaSbaaSqaaiaaikdaaeqaaaaaaaa@4295@ ; A 2 f 21 =g= A 1 f 12 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadgeadaWgaaWcbaGaaGOmaaqabaGccaWGMbWaaSbaaSqaaiaaikdacaaIXaaabeaakiabg2da9iaadEgacqGH9aqpcaWGbbWaaSbaaSqaaiaaigdaaeqaaOGaamOzamaaBaaaleaacaaIXaGaaGOmaaqabaaaaa@40DD@

unité : 1


ar
عامل الشكل بين سطحين

de
..... (zwischen zwei Flächen S1 und S2)

es
factor de forma

fi
…..

it
fattore di forma

ko
형태 계수, <두 표면 S<sub>1</sub> 과 S<sub>2</sub> 사이>

ja
形態係数

no
nb formfaktor

nn formfaktor

pl
współczynnik kształtu (między dwiema powierzchniami)

pt
factor de forma (entre duas superfícies S1 e S2)

Publication date: 1987
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