Optimization of Street Aspect Ratio for Pedestrian Comfort in Hot and Humid Climate of Nepal

Abstract

Walkable and livable cities come under the first priority of people searching for a new residential space in today’s context. In order to create a comfortable walkable condition for pedestrians, more focus should be given to shading the pathway. Among many ideas, the development of an optimum aspect ratio is paramount for improving the walkability of any street. This research is focused on developing and promoting an optimum street aspect ratio in the hot and humid road section of Lumbini Sanskritik Municipality through the use of Envi-Met software. This research involves the use of temperature and humidity data to simulate 3D street layouts in order to obtain the desired results in the form of air temperature, mean radiant temperature and

physiological equivalent temperature as outputs. This research concludes that for east- west oriented streets, the aspect ratio above 2 is favorable whereas for north-south

oriented streets, the aspect ratio of 1.5 is the optimum result. The optimum aspect ratio obtained from the simulation reduced the ambient air temperature of the same street by more than 3.5 °C, mean radiant temperature by more than 20 °C and physiological equivalent temperature by more than 12 °C. Similarly, orientation from 30° NE/210° SW to 150 ° NW/330° SE seems better for street orientation in case of Lumbini