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Area Lighting / Lighting technology, day lighting

IEV ref845-09-71

Symbol
g

en
(mutual) exchange coefficient, <between two surfaces S1 and S1, when the radiance or luminance of S1 (or S2) is the same at all points and for all directions>
quotient of the radiant or luminous flux that surface S1 (or S2) sends to surface S2 (or S1),by the radiant or luminous exitance of surface S1 (or S2)

g= Φ 2 M 1 = Φ 1 M 2 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadEgacqGH9aqpdaWcaaqaaiabfA6agnaaBaaaleaacaaIYaaabeaaaOqaaiaad2eadaWgaaWcbaGaaGymaaqabaaaaOGaeyypa0ZaaSaaaeaacqqHMoGrdaWgaaWcbaGaaGymaaqabaaakeaacaWGnbWaaSbaaSqaaiaaikdaaeqaaaaaaaa@40BC@

unit : m2

Note 1 – Since M = πL, and in the particular case where all points on S1 are seen from all points on S2

g= 1 π A 1 A 2 cos θ 1 cos θ 2 l 2 d A 1 d A 2 = 1 π G MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadEgacqGH9aqpdaWcaaqaaiaaigdaaeaaimaacqWFapaCaaWaa8qeaeaadaWdraqaamaalaaabaGaci4yaiaac+gacaGGZbGaeqiUde3aaSbaaSqaaiaaigdaaeqaaOGaeyyXICTaci4yaiaac+gacaGGZbGaeqiUde3aaSbaaSqaaiaaikdaaeqaaaGcbaGaamiBamaaCaaaleqabaGaaGOmaaaaaaaabaGaamyqamaaBaaameaacaaIYaaabeaaaSqab0Gaey4kIipaaSqaaiaadgeadaWgaaadbaGaaGymaaqabaaaleqaniabgUIiYdGccaaMe8UaaeizaiaadgeadaWgaaWcbaGaaGymaaqabaGccqGHflY1caqGKbGaamyqamaaBaaaleaacaaIYaaabeaakiabg2da9maalaaabaGaaGymaaqaaiab=b8aWbaacaWGhbaaaa@5DE8@

where l is the distance between the elements of areas dA1 and dA2 on the surfaces S1 and S2, and G is the geometric extent of the beam delimited by the boundaries of S1 and S2.

Note 2 – For two elementary areas dA1 and dA2

dg= 1 π d A 1 d Ω 1 cos θ 1 = 1 π d A 2 d Ω 2 cos θ 2 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaabsgacaWGNbGaeyypa0ZaaSaaaeaacaaIXaaabaacdaGae8hWdahaaiaabsgacaWGbbWaaSbaaSqaaiaaigdaaeqaaOGaeyyXICTaaeizaiabfM6axnaaBaaaleaacaaIXaaabeaakiabgwSixlGacogacaGGVbGaai4CaiabeI7aXnaaBaaaleaacaaIXaaabeaakiabg2da9maalaaabaGaaGymaaqaaiab=b8aWbaacaqGKbGaamyqamaaBaaaleaacaaIYaaabeaakiabgwSixlaabsgacqqHPoWvdaWgaaWcbaGaaGOmaaqabaGccqGHflY1ciGGJbGaai4BaiaacohacqaH4oqCdaWgaaWcbaGaaGOmaaqabaaaaa@5E5D@

where dΩ1 (or dΩ2) is the solid angle which the area dA2 (or dA1) subtends from the centre of dA1 (or dA2).

Note 3 – The radiance or luminance of the beam delimited by the boundaries of dA1 and dA2 is

L= 1 π dΦ dg MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadYeacqGH9aqpdaWcaaqaaiaaigdaaeaaimaacqWFapaCaaGaeyyXIC9aaSaaaeaacaqGKbGaeuOPdyeabaGaaeizaiaadEgaaaaaaa@4043@


[SOURCE: 845-01-33]


fr
coefficient d'échange (mutuel), <entre deux surfaces S1 et S2 lorsque la luminance énergétique ou lumineuse de S1 (ou S2) est la même en tous points et dans toutes les directions> m
quotient du flux énergétique ou lumineux que la surface S1 (ou S2) envoie sur la surface S2 (ou S1), par l'exitance énergétique ou lumineuse de la surface S1 (ou S1)

g= Φ 2 M 1 = Φ 1 M 2 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadEgacqGH9aqpdaWcaaqaaiabfA6agnaaBaaaleaacaaIYaaabeaaaOqaaiaad2eadaWgaaWcbaGaaGymaaqabaaaaOGaeyypa0ZaaSaaaeaacqqHMoGrdaWgaaWcbaGaaGymaaqabaaakeaacaWGnbWaaSbaaSqaaiaaikdaaeqaaaaaaaa@40BC@

unité : m2

Note 1 – Puisque M = πL, et dans le cas particulier où tous les points de S1 sont vus de tous les points de S2

g= 1 π A 1 A 2 cos θ 1 cos θ 2 l 2 d A 1 d A 2 = 1 π G MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadEgacqGH9aqpdaWcaaqaaiaaigdaaeaaimaacqWFapaCaaWaa8qeaeaadaWdraqaamaalaaabaGaci4yaiaac+gacaGGZbGaeqiUde3aaSbaaSqaaiaaigdaaeqaaOGaeyyXICTaci4yaiaac+gacaGGZbGaeqiUde3aaSbaaSqaaiaaikdaaeqaaaGcbaGaamiBamaaCaaaleqabaGaaGOmaaaaaaaabaGaamyqamaaBaaameaacaaIYaaabeaaaSqab0Gaey4kIipaaSqaaiaadgeadaWgaaadbaGaaGymaaqabaaaleqaniabgUIiYdGccaaMe8UaaeizaiaadgeadaWgaaWcbaGaaGymaaqabaGccqGHflY1caqGKbGaamyqamaaBaaaleaacaaIYaaabeaakiabg2da9maalaaabaGaaGymaaqaaiab=b8aWbaacaWGhbaaaa@5DE8@

l est la distance entre les aires élémentaires dA1 et dА2 prises sur les surfaces S1 et S2, et G l'étendue géométrique du faisceau délimité par les contours de S1 et S2.

Note 2 – Pour deux aires élémentaires dA1 et dA2

dg= 1 π d A 1 d Ω 1 cos θ 1 = 1 π d A 2 d Ω 2 cos θ 2 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaabsgacaWGNbGaeyypa0ZaaSaaaeaacaaIXaaabaacdaGae8hWdahaaiaabsgacaWGbbWaaSbaaSqaaiaaigdaaeqaaOGaeyyXICTaaeizaiabfM6axnaaBaaaleaacaaIXaaabeaakiabgwSixlGacogacaGGVbGaai4CaiabeI7aXnaaBaaaleaacaaIXaaabeaakiabg2da9maalaaabaGaaGymaaqaaiab=b8aWbaacaqGKbGaamyqamaaBaaaleaacaaIYaaabeaakiabgwSixlaabsgacqqHPoWvdaWgaaWcbaGaaGOmaaqabaGccqGHflY1ciGGJbGaai4BaiaacohacqaH4oqCdaWgaaWcbaGaaGOmaaqabaaaaa@5E5D@

où dΩ1 (ou dΩ2) est l'angle solide sous lequel l'aire élémentaire dA2 (ou dA1) est vue du centre de dA1 (ou dA2).

Note 3 – La luminance énergétique ou lumineuse du faisceau délimité par les contours de dA1 et dA2 est

L= 1 π dΦ dg MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbbjxAHXgaruavP1wzZbItLDhis9wBH5garmWu51MyVXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaiqaciWacmGadaGadeaabaGaaqaaaOqaaiaadYeacqGH9aqpdaWcaaqaaiaaigdaaeaaimaacqWFapaCaaGaeyyXIC9aaSaaaeaacaqGKbGaeuOPdyeabaGaaeizaiaadEgaaaaaaa@4043@


[SOURCE: 845-01-33]


ar
معامل التبادل ( المشترك)

de
gegenseitiger Austauschkoeffizient (zwischen zwei Flächen S1 und S2 für den Fall, dass die Strahldichte bzw. Leuchtdichte von S1 (oder S2) in allen Punkten und in allen Richtungen gleich ist), m
Austauschkoeffizient (zwischen zwei Flächen S1 und S2 für den Fall, dass die Strahldichte bzw. Leuchtdichte von S1 (oder S2) in allen Punkten und in allen Richtungen gleich ist), m

es
coeficiente de cambio (mutuo)

fi
keskinäisheijastumisen siirtokerroin

it
coefficiente di scambio

ko
상호 교환계수, 두 표면사이

ja
相互交換係数

no
nb (gjensidig) utvekslingskoeffisient

nn (gjensidig) utvekslingskoeffisient

pl
współczynnik wymiany wzajemnej (miedzy dwiema powierzchniami, gdy luminancja energetyczna lub świetlna tych powierzchni jest jednakowa we wszystkich kierunkach)
współczynnik wymiany

pt
coeficiente de troca (mútua) (entre duas superfícies S1 e S2 quando a luminância energética ou luminosa de S1 ou S2 é a mesma em todos os pontos e me todas as direcções)

Publication date: 1987
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