Solar optical properties
Any optical material obey the following law under any given wave length: T+a+p=1
T, a, and p are function of А,
Total solar heat excluded-16% |
Total solar heat admitted-84% |
Figure 6-10 Distribution of solar radiation falling on clear plate glass. |
Where t = transmittance
A = absorptance p = reflectance X = wave length (m)
Transmitted solar radiation-80% |
Further,
А, f = c
Where f = frequency (HZ)
C = light speed (3xl08 m/s)
Architectural glass:
Opaque to long-wave radiation Transparent to short-wave radiation (sun light)
This is the well-known greenhouse effect.
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