Parameterization of traditional domed-roofs insolation in hot-arid climates in Aswan, Egypt

Abstract

This paper is part of a continuing study that aims at investigating the relationship between the amount of the solar radiation received on curved roofs and their geometrical configurations. It introduces computational method as a tool for the parametric approach in passive building design, enhancing the use and design of traditional domed-roof forms in hot-arid climates. The main objective behind this is to explore multiple configurations of domed-roof forms (semicircular, pointed, and faceted) and perform insolation investigations on them to discover the form that minimizes the quantity of received solar radiation with regard to variations in the received average daily solar irradiance (kW h/m2/day). The geographical latitude of Aswan (23.58°N) has been chosen to represent hot-arid regions of southern Egypt. Rhinoceros’s Grasshopper, a graphical algorithm editor, its component of gECO, and Autodesk’s Ecotect are utilized to establish such approach. The findings of the paper confirm that the maximum average daily solar irradiance is often recorded at flat surfaces. While the value varies from dome form to another, it decreases with the increase of the concaveness of domed-roof forms. The findings accomplish that domed-roof forms facilitate a significant decrease in the received average daily solar irradiance above their surface, when compared to flat surface, in both summer and winter. The paper concludes that domed-roof forms have great impact on minimizing the intensity of the received solar irradiance by maximizing the ratio between the dome’s height and its radius. Thus, they reduce the required energy for cooling in hot climates, and consequently, provide indoor thermal comfort.