DEVELOPING SHADING ENVELOPE FOR PEDESTRIAN THERMAL COMFORT ON STREETS OF ARBA MINCH TOWN, ETHIOPIA

Abstract

The thermal environment outside has an impact on human comfort, health, and physical performance, particularly in cities with hot and dry climates, such as Arba Minch, Ethiopia, which is situated in the tropical belt. According to the outdoor thermal comfort assessment result, there is a clear difference in a human thermal comfort sensation value in sunny versus shaded areas due to the primary contribution of solar radiation. To maintain outdoor thermal comfort on a nearby street Shadow envelope design for daytime is recommended as it reduces solar radiation and contributes to a more pleasant urban environment for pedestrians. The prevailing climate conditions and solar sun path have been considered and analyzed to construct and shape the shading envelope appropriately. By taking typical plot size along the eight-cardinal orientation of streets, the envelope was constructed using Rhinoceros, a graphical programming interface Grasshopper, and an open-source weather analysis tool Ladybug. The research concludes that shading envelope-based urban design is recommended and establishing heights must be included in the Conventional zoning in cities that have a hot-humid climate like Arba Minch as it is a main contributing factor to the health of city pedestrians. E-W and N-S streets are exposed to the sun at critical 12:00 am and 1:00 pm local times all year, which is highly exposed to solar radiation. To shade those streets, recommended to plant deciduous trees on the street sidewalk. Finally, as many studies shows that although computer models are powerful, physical models are still better Therefore, a Solar Geometry Demonstration Heliodon use to validate the final design.