A PARAMETRIC STUDY OF LIGHT SHELF SYSTEM PERFORMANCE FOR SOUTH ORIENTION IN HOT ARID ZONE (A case study of a hypothetical office building in New Cairo area)

Document Type : Scientific and technological

Author

Teacher Assistant of Architecture , El Safwa High Institute for Engineering and Technology ,Egypt.

Abstract

In this daylighting study, a parametric approach was implemented, where all possible combinations of the various design parameters for the two design elements of the light shelf system (light shelf and room specifications) were computed.  This generated a total of “819” cases that were tested exploring experimental hypothetical deep office room, facing South orientation with no external obstruction. The experimental tests of the parametric light shelf system have been executed through using Diva-for-Rhino (Grasshopper). The performance results were performed according to the Illuminating Engineering Society (IES) metrics, Spatial Daylight Autonomy (sDA 300/50%), Annual Sunlight Exposure (ASE 1000/250 h), Daylight Availability as well as Annual Daylight Glare Probability (DGP), in addition to the metric value for total Annual Energy consumption (tAEC).
The result analysis of the most successful tested study cases that have contributed design indicators for optimizing the performance of light shelf design parameters. In order to extent and maximize the positive influence of each design parameter within the design combinations that have proved successful. The selected successful tested case studies are the alternatives designs of light shelf systems for deep office spaces in new Cairo area, as models for applying light shelf system in the south direction in areas of hot climates under clear sky conditions. Among defined successful study cases, specific study cases will be selected as eligible samples for development,  which by optimizing the performance of all their design parameters; be able to define the design aspects of advanced design cases of parametric light shelf systems for deep office spaces with optimum overall performance facing South orientation. This will be followed by subsequent future studies in the context of the trend towards defining the main design aspects, characteristics and executive specifications of sophisticated light shelf design systems in all main four major orientations.

Keywords


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