Revealing Urban Morphology and Outdoor Comfort through Genetic Algorithm-Driven Urban Block Design in Dry and Hot Regions of China

Abstract

In areas with a dry and hot climate, factors such as strong solar radiation, high temperature, low humidity, dazzling light, and dust storms can tremendously reduce people’s thermal comfort. Therefore, researchers are paying more attention to outdoor thermal comfort in urban environments as part of urban design. This study proposed an automatic workflow to optimize urban spatial forms with the aim of improvement of outdoor thermal comfort conditions, characterized by the universal thermal climate index (UTCI). A city with a dry and hot climate—Kashgar, China—is further selected as an actual case study of an urban block and Rhino & Grasshopper is the platform used to conduct simulation and optimization process with the genetic algorithm. Results showed that in summer, the proposed method can reduce the averaged UTCI from 31.17 to 27.43 °C, a decrease of about 3.74 °C, and reduce mean radiation temperature (MRT) from 43.94 to 41.29 °C, a decrease of about 2.65 °C.

Subtractive Building Massing for Performance-Based Architectural Design Exploration: A Case Study of Daylighting Optimization

“…In order to overcome the lack of topological variability, other researchers have proposed sophisticated parametric modelling approaches to offering discrete formal variability of the generated building massing. One commonly used approach is to include several massing algorithms, respectively describing different building massing forms in one parametric model, and select one of these algorithms to create the building massing each time [6,24,25]. This approach is often used in design problems at the urban scale, and the desired urban form diversity can be simply achieved by varying permutations and combinations of different forms over multiple buildings.…”

“…This approach is often used in design problems at the urban scale, and the desired urban form diversity can be simply achieved by varying permutations and combinations of different forms over multiple buildings. Nault et al [6] and Xiaodong et al [25] used this approach to create neighborhood-scale and urban block design based on a set of basic building forms for energy-daylighting optimization and outdoor thermal comfort optimization. Another approach is to create building massings composed of various small mass units.…”

“…In contrast, this research explores the idea that it may be possible to reuse a parametric model for different design contexts if generic design (building massing) strategies can be represented by the parametric model [35]. Recently, a few studies have attempted to develop design support systems, including predefined generic building forms, to reduce the effort and time invested in parametric modelling, thereby allowing architects to carry out streamlined performance-based optimization processes without the interruption of parametric modelling [6,25]. However, as pointed out in these studies, offering sufficient topological variability in the design generated, again, presents a significant challenge for developers.…”

Identifying key determinants for building energy analysis from urban building datasets

“…Early studies usually started from constructing a relationship between the urban micro-climate and urban design to reveal how the urban morphology influences the urban micro-climate and, in turn, the energy usage [7,8]. Urban and building forms are the key factors that influence the urban micro-climate, such as solar radiation [9], wind environment [10], as well as the related energy demand [11,12]. Yuan et al highlighted the effect of the urban morphologies on the urban heat island (UHI) effect and integrated a geographic information system and computational fluid dynamics for modeling the impact of urban morphology on the heat dispersion [13].…”

Investigations on the Winter Thermal Environment of Bedrooms in Zhongxiang: A Case Study in Rural Areas in Hot Summer and Cold Winter Region of China

“…The results showed that urban areas experience stronger warming trends than non-urban areas, demonstrating the notable effects of urbanization [3]. Xu et al [4] proposed an automatic workflow to optimize urban spatial forms with the aim of improving outdoor thermal comfort conditions as characterized by the universal thermal climate index, and applied this method in Kashgar, China. Ma et al [5] conducted field measurements and numerical simulations to analyze thermal sensation in a tourism area in Fo Shan city Many studies of indoor thermal environment/comfort were conducted in urban areas.…”