The Experimental and Numerical Analysis of a Lightpipe using a Simulation Software

Authors: M. Paroncini, F. Corvaro, G. Nardini, S. Pistolesi

Abstract:

A lightpipe is an about 99 percent specular reflective mirror pipe or duct that is used for the transmission of the daylight from the outside into a building. The lightpipes are usually used in the daylighting buildings, in the residential, industrial and commercial sectors. This paper is about the performances of a lightpipe installed in a laboratory (3 m x 2.6 m x 3 m) without windows. The aim is to analyse the luminous intensity distribution for several sky/sun conditions. The lightpipe was monitored during the year 2006. The lightpipe is 1 m long and the diameter of the top collector and of the internal diffuser device is 0.25 m. In the laboratory there are seven illuminance sensors: one external is located on the roof of the laboratory and six internal sensors are connected to a data acquisition system. The internal sensors are positioned under the internal diffusive device at an height of 0.85 m from the floor to simulate a working plane. The numerical data are obtained through a simulation software. This paper shows the comparison between the experimental and numerical results concerning the behavior of the lightpipe.

Keywords: Daylighting, Desktop Radiance, Lightpipe.

Digital Object Identifier (DOI): doi.org/10.5281/zenodo.1078889

References:

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[3] M. Paroncini, F. Corvaro, G. Nardini, S. Pistolesi "The performance analysis of three lightpipes using a simulation software," International workshop and 7th Annex 45 Expert Meeting.,2008.
[4] Lawrence Berkeley National Laboratory Environmental Energy Technologies Division Building Technologies Department: Desktop Radiance 2.0 beta User Manual, 2000.
[5] M. Paroncini, B. Calcagni, , "Performance of a Light Capturing System to Transport and Improve Natural Light Within Buildings", LuxEuropa 2005, Berlin.