Simulating the Daylight Performance of Fenestration Systems and Spaces of Arbitrary Complexity: The IDC Method

TitleSimulating the Daylight Performance of Fenestration Systems and Spaces of Arbitrary Complexity: The IDC Method
Publication TypeConference Paper
Year of Publication1993
AuthorsKonstantinos M. Papamichael, Liliana O. Beltran
Conference Name3rd International Conference of the International Building Performance Simulation Association, Building Simulation 93
Conference LocationAdelaide, Australia
Call NumberLBL-33945
Abstract

A new method to simulate the daylight performance of fenestration systems and spaces is presented. This new method, named IDC (Integration of Directional Coefficients), allows the simulation of the daylight performance of fenestration systems and spaces of arbitrary complexity, under any sun, sky and ground conditions. The IDC method is based on the combination of scale model photometry and computer-based simulation. Physical scale models are used to experimentally determine a comprehensive set of directional illuminance coefficients at reference points of interest, which are then used in analytical, computer-based routines, to determine daylight factors or actual daylight illuminance values under any sun, sky and ground conditions.

The main advantage of the IDC method is its applicability to any optically complex environment. Moreover, the computer-based analytical routines are fast enough to allow for hourly simulation of the daylight performance over the course of an entire year. However, the method requires appropriate experimental facilities for the determination of the Directional Coefficients. The IDC method has been implemented and used successfully in inter-validation procedures with various daylight simulation computer programs. Currently, it is used to simulate the daylight performance of fenestration systems that incorporate optically complex components, such as Venetian blinds, optically treated light shelves and light pipes.

LBNL Report Number

LBL-33945