This research developed the Optical Light Pipe (OLP) as a feasible solution to
solve the problem of insufficient daylighting in deep plan office spaces for predominantly
sunny climates. It further combined the OLP with a Specular Light Shelf
(SLS) to achieve uniform daylighting.
This research was performed with an experimental setup of two 1:4 scale models
of deep plan office spaces, modified from an earlier research on optical light pipe at
College Station, TX. Blinds and shading devices were installed on the south façade to
provide daylight to the front zone of a 20 feet by 30 feet office module. The back zone
was daylit by the OLP hidden in the plenum. The existing OLP design was optimized
through computer aided ray-tracing. The SLS design was based on an earlier prototype
designed at Lawrence Berkeley National Labs (LBNL).
Results were based on observations made on clear and cloudy sky days between
February 3rd and March 17th. The OLP achieved more than 300 lux of average
workplane illuminance for 7.4 hours, when global horizontal illuminance was greater
than 40,000 lux. It also achieved 200 lux of illuminance higher than an earlier prototype (Martins-Mogo, 2005) on workplane between 1000hrs and 1630hrs. It exhibited a glare
free daylight distribution with luminance ratios well within prescribed limits on most of
the vertical surfaces, with a relatively uniform illuminance distribution on back
taskplane. OLP was better than windows with blinds and shading at providing diffuse
daylight in backzone on a cloudy day, when global horizontal illuminance was greater
than 20,000 lux.
The OLP used in combination with SLS achieved more than 500 lux of average
workplane illuminance for 6 hours, when global horizontal illuminance was greater than
40,000 lux. SLS also produced more uniform illuminance levels on the workplane at all
times and on the leftwall at most times. However, it produced non-uniform luminance
distribution on walls and ceiling and luminance ratios higher than allowable limits on the
sidewall for some morning hours, and hence needed further refinement in design.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-2873 |
| Date | 15 May 2009 |
| Creators | Upadhyaya, Kapil |
| Contributors | Beltran, Liliana O. |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | Book, Thesis, Electronic Thesis, text |
| Format | electronic, application/pdf, born digital |
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