@article {31851, title = {Split-pane electrochromic window control based on an embedded photometric device with real-time daylighting computing}, journal = {Building and Environment}, volume = {161}, year = {2019}, month = {08/2019}, pages = {106229}, abstract = {

Well-designed electrochromic (EC) glazing control can improve the energy performance of buildings and visual comfort of occupants in highly glazed buildings. This paper designed and demonstrated a compact integrated EC glazing automation system to control tint states of a split-pane EC window according to variations of sky conditions. The control is based on monitoring the luminance distribution of the sky and real-time lighting computation for a building interior, using an embedded photometric device (EPD). It optimizes tint states of EC glazing to offer sufficient daylight provision and temper discomfort glare for occupants, which potentially mitigates excessive solar heat gain. {\textquoteright}In-situ{\textquoteright} experiments were conducted in a full-scale testbed to demonstrate the daylighting performance under various sky conditions. Experimental results showed 83\% of the working time for work-plane illuminance (WPI) and 95\% of the time for daylight glare probability (DGP) were constrained in comfort range (WPI[500, 2000] lux, DGP\ <=\ 0.35) by the automated EC glazing (controlled by EPD) under clear skies; 68\% of the time for WPI and 94\% of the time for DGP in confined range under clear skies with thin clouds; 62\% of the time for WPI and 85\% of the time for DGP in confined range under partly cloudy skies.

}, keywords = {daylighting, electrochromic, Embedded Controller, HDR, windows}, issn = {03601323}, doi = {10.1016/j.buildenv.2019.106229}, url = {https://linkinghub.elsevier.com/retrieve/pii/S0360132319304391}, author = {Yujie Wu and Taoning Wang and Eleanor S. Lee and J{\'e}r{\^o}me H. K{\"a}mpf and Jean-Louis Scartezzini} } @article {11582, title = {Bi-Directional Transmission Properties of Venetian Blinds: Experimental Assessment Compared to Ray-Tracing Calculations}, journal = {Solar Energy}, volume = {78}, number = {2}, year = {2005}, pages = {187-198}, abstract = {

An accurate evaluation of daylight distribution through advanced fenestration systems (complex glazing, solar shading systems) requires the knowledge of their Bidirectional light Transmission (Reflection) Distribution Function BT(R)DF. An innovative equipment for the experimental assessment of these bi-directional functions has been developed, based on a digital imaging detection system. An extensive set of BTDF measurements was performed with this goniophotometer on Venetian blinds presenting curved slats with a mirror coating on the upper side. In this paper, the measured data are compared with ray-tracing results achieved with a virtual copy of the device, that was constructed with a commercial ray-tracing software. The model of the blind was created by implementing the measured reflection properties of the slats coatings in the ray-tracing calculations. These comparisons represent an original and objective validation methodology for detailed bi-directional properties for a complex system; the good agreement between the two methods, yet presenting very different parameters and assessment methodologies, places reliance both on the digital-imaging detection system and calibration, and on the potentiality of a flexible calculation method combining ray-tracing simulations with simple components measurements.

}, author = {Marilyn Andersen and Michael D. Rubin and Rebecca Powles and Jean-Louis Scartezzini} } @article {11635, title = {Comparison Between Ray-Tracing Simulations and Bi-Directional Transmission Measurements on Prismatic Glazing}, journal = {Solar Energy}, volume = {74}, number = {2}, year = {2003}, month = {02/2003}, pages = {157-173}, chapter = {157}, abstract = {

Evaluation of solar heat gain and daylight distribution through complex window and shading systems requires the determination of the bi-directional transmission distribution function (BTDF). Measurement of BTDF can be timeconsuming, and inaccuracies are likely because of physical constraints and experimental adjustments. A general calculation methodology, based on more easily measurable component properties, would be preferable and would allow much more flexibility. In this paper, measurements and calculations are compared for the specific case of prismatic daylight-redirecting panels. Measurements were performed in a photogoniometer equipped with a digital-imaging detection system. A virtual copy of the photogoniometer was then constructed with commercial ray-tracing software. For the first time, an attempt is made to validate detailed bi-directional properties for a complex system by comparing an extensive set of experimental BTDF data with ray-tracing calculations. The results generally agree under a range of input and output angles to a degree adequate for evaluation of glazing systems. An analysis is presented to show that the simultaneously measured diffuse and direct components of light transmitted by the panel are properly represented. Calculations were also performed using a more realistic model of the source and ideal model of the detector. Deviations from the photogoniometer model were small and the results were similar in form. Despite the lack of an absolute measurement standard, the good agreement in results promotes confidence in both the photogoniometer and in the calculation method.\ 

}, doi = {10.1016/S0038-092X(03)00115-4}, author = {Marilyn Andersen and Michael D. Rubin and Jean-Louis Scartezzini} } @book {11676, title = {Daylight in Buildings. A Source Book on Daylighting Systems and Components}, year = {2001}, note = {

Download: Daylight in Buildings
A hard copy of the book may be obtained by sending a request to Ellen Thomas at\ EllenThomas@lbl.gov.\ Only one copy per individual, U.S. or Canadians only.\  If you reside elsewhere, go to\ http://task21.iea-shc.org/to find out how to obtain a copy in your country.\ 

}, url = {https://facades.lbl.gov/daylight-buildings-source-book-daylighting-systems}, author = {Nancy Ruck and {\O}yvind Aschehoug and Sirri Aydinli and Jens Christoffersen and Gilles Courret and Ian Edmonds and Roman Jakobiak and Martin Kischkoweit-Lopin and Martin Klinger and Eleanor S. Lee and Laurent Michel and Jean-Louis Scartezzini and Stephen E. Selkowitz} }