Ingineria Iluminatului - Journal of Lighting Engineering - Prof. Florin ...

Figure 13 General recurrence laws – true case with
losses
The fluxes can be given as a function of the
injection flux of one lamp (unilateral light
source) or two lamps (bilateral light source), or
as a function of the fluxes entering each unit
section.
5. Production of an optical model of a light
pipe through an APILUX simulation
Given that the simulation of a light pipe is very
complicated owing to the size of the prismatic
microstructures, we produced a simplified
optical model using the APILUX software,
which allows the predicted illumination to be
calculated.
The model design comprises a series of
transparent yet reflective concave mirrors
angled at 45°, that can reproduce the same
guiding and diffusion functions of the simulated
light pipe. The reflectance, transmittance and
absorbance in a case with losses, are set by
applying the previously determined recurrence
laws, with each section of the light pipe being
simulated by a mirror. The number of mirrors
per model is set such that its distribution of light
on the surface of a detector is close to that of the
actual light pipe.
The model, injected with light from a point
source simulating the light pipe source lamp, is
placed a certain distance from a detector (see
Figure 14) that is capable of measuring all the
light incident on its surface and drawing its
isolux curves (see Figure 15).
By placing the model inside a volume
detector (see Figure 16), we can see how the
light is distributed in the room and make various
sections (see Figure 17, 18 and 19).
Figure 14 3D representation of a 1 m light pipe
Figure 15 3D representation of a 6 m light pipe
Figure 16 Vertical longitudinal section of the model
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