Search Results (140)

Improving outdoor thermal comfort is a critical objective in urban design, particularly in densely built urban environments. Elevated semi-open spaces—outdoor areas located beneath raised building structures—have been recognized for enhancing pedestrian comfort by improving airflow and shading. However, previous studies primarily focused on warm or temperate climates, leaving a significant research gap regarding their thermal performance in cold climate zones characterized by extreme seasonal variations. Specifically, few studies have investigated how these spaces perform under conditions typical of northern Chinese cities like Xi’an, which is explicitly classified within the Cold Climate Zone according to China’s national standard GB 50176-2016 and experiences both severe summer heat and cold winter conditions. To address this gap, we conducted field measurements and numerical simulations using the ENVI-met model (v5.0) to systematically evaluate the microclimatic performance of elevated ground-floor spaces in Xi’an. Key microclimatic parameters—including air temperature, mean radiant temperature, relative humidity, and wind velocity—were assessed during representative summer and winter conditions. Our findings indicate that the height of the elevated structure significantly affects outdoor thermal comfort, identifying an optimal elevated height range of 3.6–4.3 m to effectively balance summer cooling and winter sheltering needs. These results provide valuable design guidance for architects and planners aiming to enhance outdoor thermal environments in cold climate regions facing distinct seasonal extremes. Full article

Urban residential design influences local microclimates and human thermal comfort. This study combines empirical microclimate data with remotely sensed data on tree canopy cover, housing lot size, surface permeability, and roof colour to examine thermal differences between three newly built and three established residential suburbs in Western Sydney, Australia. Established areas featured larger housing lots and mature street trees, while newly developed suburbs had smaller lots and limited vegetation cover. Microclimate data were collected during summer 2021 under both heatwave and non-heatwave conditions in full sun, measuring air temperature, relative humidity, wind speed, and wet-bulb globe temperature (WBGT) as an index of heat stress. Daily maximum air temperatures reached 42.7 °C in new suburbs, compared to 39.3 °C in established ones (p < 0.001). WBGT levels during heatwaves were in the “extreme caution” category in new suburbs, while remaining in the “caution” range in established ones. These findings highlight the benefits of larger green spaces, permeable surfaces, and lighter roof colours in the context of urban heat exposure. Maintaining mature trees and avoiding dark roofs can significantly reduce summer heat and improve outdoor thermal comfort across a range of conditions. Results of this work can inform bottom-up approaches to climate-responsive urban design where informed homeowners can influence development outcomes. Full article

Against the background of the global concern for environmental protection and the prevalence of the green building concept, the requirements for building design are increasing, as are the technological content and functional requirements. Meanwhile, the urgency to address challenges related to the ecological environment and performance requirements has become increasingly pronounced. Taking a dormitory building in China as an example. Autodesk Revit 2018 software is employed in this study to establish a building information modeling (BIM). Green building software (GBSWARE) simulates and analyzes outdoor wind environment, indoor thermal comfort, calculates building energy conservation, does daylighting analysis, and calculates building daylighting. Although the building’s energy-saving design aligns with the requirements, the lighting and indoor thermal comfort of the rooms do not meet the standards. Additionally, the outdoor wind environment has problems with the wind zone and a wind speed amplification coefficient that surpasses the limit. The thermal environment within the residential building fails to satisfy the requirements. This study leverages a BIM-based model for multifaceted applications, integrating tailored retrofit strategies that align with the building’s inherent characteristics and detailed analyses of its components. By harnessing the building’s energy-saving potential, it enhances energy use efficiency, offering a valuable reference for the conceptual design of green buildings and energy-efficient retrofits. Full article

During their evolution, Sino-Tibetan temples have been influenced by multiple factors, including history, geography, and climate, resulting in a variety of distinctive spatial layouts. Through performance simulations, many traditional construction methods have been found to still offer valuable insights for contemporary architectural designs. This study selects several typical spatial layouts that emerged during the evolutionary process as research subjects and uses the building simulation software (Ladybug Tools 1.7.0) for simulation. Comparative analysis of the thermal and wind environment simulation results reveals that the layout with directly connected front and rear spaces offers a 10% higher ventilation efficiency than the courtyard-inserted layout. Although the wind field is relatively uniform, excessive influx of hot air disrupts the indoor thermal environment. When a buffer space is introduced as a transition, ventilation efficiency decreases by approximately 12%, but indoor dissatisfaction decreases by an average of 3%. The central courtyard and direct separation layouts enhance ventilation by altering the wind pressure difference between the indoor and outdoor environments. Under conditions of weak wind, indoor comfort satisfaction remains stable between 75% and 78%. This study re-examines the spatial forms of Sino-Tibetan temples, analyzing the pros and cons of various spatial layouts from the perspective of architectural performance and proposing strategies for their application in modern design. Furthermore, the conclusions of this research contribute to the future protection or renovation of these temples without compromising the original architectural concept. Full article

With the continual expansion of global urbanization and population growth, urban energy demands have intensified, and anthropogenic activities have precipitated profound shifts in the global climate. These climatic changes directly alter urban environmental conditions, which in turn exert indirect effects on human physiological function. Consequently, the comfort of outdoor community environments has emerged as a critical metric for assessing the quality of human habitation. Although existing studies have focused on improving singular environmental factors—such as wind or thermal comfort—they often lack an integrated, multi-factor coupling mechanism, and adaptive strategy systems tailored to hot-summer, cold-winter regions remain underdeveloped. This study examines the Minhe Community in Qian’an City to develop a performance evaluation framework for outdoor spaces grounded in subjective comfort and to close the loop from theoretical formulation to empirical validation via an interdisciplinary approach. We first synthesized 25 environmental factors across eight categories—including wind, thermal, and lighting parameters—and applied the Analytic Hierarchy Process (AHP) to establish factor weights, thereby constructing a comprehensive model that encompasses both physiological and psychological requirements. Field surveys, meteorological data collection, and ENVI-met (V5.1.1) microclimate simulations revealed pronounced issues in the community’s wind distribution, thermal comfort, and acoustic environment. In response, we proposed adaptive interventions—such as stratified vegetation design and permeable pavement installations—and validated their efficacy through further simulation. Post-optimization, the community’s overall comfort score increased from 4.64 to 5.62, corresponding to an efficiency improvement of 21.3%. The innovative contributions of this research are threefold: (1) transcending the limitations of single-factor analyses by establishing a multi-dimensional, coupled evaluation framework; (2) integrating AHP with ENVI-met simulation to realize a fully quantified “evaluation–simulation–optimization” workflow; and (3) proposing adaptive strategies with broad applicability for the retrofit of communities in hot-summer, cold-winter climates, thereby offering a practical technical pathway for urban microclimate enhancement. Full article

Improving students’ thermal comfort in university courtyards and indoor spaces promotes walkability, enhances livability, and fosters social interaction among students. This study aims to improve students’ outdoor thermal comfort in university courtyards, to reduce heat transfer to classrooms, and to accordingly reduce energy consumption in university buildings in hot arid climates. Thus, the proposed coupled methodology for the case study, the Faculty of Agriculture, New Sohag University, Egypt, consists of three stages. First, monitoring and questionnaire surveys were conducted in the open courtyard and the classroom to obtain air temperature, wind speed, thermal image, and CO₂ and thermal comfort analysis. Secondly, the Envi-met model was used to investigate the impact of six improvement solutions on improving thermal comfort in the courtyard. Third, retrofitting strategies in the building envelope were evaluated to decrease heat transfer and energy consumption by DesignBuilder software. Consequently, the findings revealed a high outdoor air temperature, which causes discomfort for students. Hence, the simulation results concluded that the significant reduction of physiological equivalent temperature (PET), which ranged between 11.1 °C and 13.9 °C, occurred after applying the hybrid improvement solutions (vegetation area and semi-shading or pergola-shading). Moreover, integrating a combination of retrofitting strategies into the faculty buildings contributed to a 30% reduction in energy consumption. Ultimately, the proposed methodology aims to assist architects and urban designers in the early design stages by providing the appropriate environmental solutions for the universities’ courtyards and buildings in hot arid climates. Full article

Urbanization and climate change present increasing challenges to outdoor human thermal comfort, particularly in university campuses where academic, social, and recreational activities converge. This study assesses microclimatic risk factors along the main avenue of the NOVA FCT campus by analyzing outdoor human thermal comfort using the physiologically equivalent temperature (PET) and modified PET (mPET) indices. Field measurements of air temperature, humidity, wind velocity, and radiation were conducted at multiple Points Of Interest (POIs) to evaluate thermal stress levels and identify critical zones of discomfort. Results indicate significant spatial and temporal variations in thermal stress, with sun-exposed areas (G2) experiencing PET values exceeding 50 °C, during peak summer hours, while shaded locations (G1) showed substantial thermal relief (PET reductions up to 27 °C between G1 and G2 POIs). Wind velocity and urban morphology played crucial roles in modulating microclimatic conditions. Wind velocity above 2.0 m/s was associated with perceptible thermal relief (3–8 °C PET/mPET reduction), especially in narrow, shaded passages. Significant spatial variability was observed, linked to differences in urban morphology, surface materials, and vegetation coverage. This research provides actionable insights for urban planners and campus administrators, contributing to the development of more sustainable and thermally comfortable outdoor environments in educational settings. Full article

This study collected site and spatial morphological data from 63 typical aging community activity spaces and extracted 12 spatial types through statistical analysis. A parametric modeling tool was used to generate spatial models. Based on clearly defined design variables and constraints, the NSGA-II multi-objective optimization algorithm was applied to minimize summer thermal discomfort, maximize winter thermal comfort, and maximize annual average sunlight duration, resulting in 342 Pareto optimal solutions. The study first explored the linear relationships between spatial morphology and environmental performance using the Spearman method. It then integrated ensemble learning and the interpretable machine learning model SHAP to reveal nonlinear relationships and boundary effects. The results of the two methods complemented and reinforced each other. Based on a comparison of these two approaches, morphological indicators showing significant differences were selected for attribution and sensitivity analyses, clarifying the mechanisms by which spatial morphological parameters influence environmental performance and identifying their critical thresholds. Key findings include the following: (1) the UTCI-S exhibits significant negative linear correlations with the open space ratio (OSR) and spatial crowding density (SCD); the UTCI-W shows negative linear correlations with canopy coverage (CVH) and wind speed (WS); and a positive linear correlation exists between the sky view factor (SVF) and AV.SH. (2) Boundary effects and threshold intervals of critical morphological parameters were identified as follows. The open space ratio should be controlled to 10–15%, the shrub–tree layer coverage to 0.013–0.0165%, and the average building height to 3.1–3.8 m. (3) Spatial layout principles demonstrate that placing fully enclosed spaces (E-2) and semi-enclosed spaces (S-1/S-3) on the northern side, as well as semi-enclosed spaces (S-1/S-2) and circulation spaces (C-3) on the southern side, significantly enhance microclimatic performance. These findings provide quantitative guidelines for community space design in cold regions and offer data support for creating outdoor environments that meet the comfort needs of the elderly. Full article

Optimizing the wind environment within university dormitory areas is essential for ensuring student safety, enhancing living comfort, and improving building energy efficiency. In this study, the wind environment of multi-story university dormitories in cold regions is comprehensively investigated through computational fluid dynamics (CFD) simulations conducted with the PHONECIS software (version 2019), combined with orthogonal experimental design methods for systematic analysis and optimization. Through orthogonal experimental design, the effects of key morphological parameters—including building layout, length, width, and height—on the near-ground wind environment were evaluated. Among these, building width exerted the greatest influence, followed by building length, layout form, and finally building height. Based on the analysis, the optimal design scheme features a staggered building layout, with individual dormitory buildings measuring 60 m in length, 16 m in width, and 11.4 m in height. This optimized design was implemented in the multi-story dormitory area of the eastern section of Chang’an University’s New Campus. A comparative analysis of wind speed distribution before and after optimization, conducted specifically for the outdoor spaces during the winter season, revealed that the average near-ground wind speed was reduced from 3.3 m/s to 2.7 m/s, achieving an 18% reduction. The staggered arrangement and adjusted building proportions effectively dispersed airflow, mitigated high-velocity zones, and significantly enhanced outdoor wind comfort and pedestrian safety. This study introduces a morphology–wind environment coupling strategy from an architectural perspective to guide the design of dormitory buildings in cold regions. Rather than focusing on mathematical modeling, the research emphasizes design-oriented outcomes aimed at informing and optimizing practical architectural solutions for safer, more comfortable, and energy-efficient campus living environments. Full article

Enclosed courtyards with partially ground floor pilotis represent a prevalent architectural spatial configuration in hot-humid regions, where the shaded outdoor areas serve as frequently utilized spaces for heat avoidance and rest. This study employed a combined approach of ENVI-met simulations and field measurements to investigate the wind and thermal environment in the shaded areas of courtyards under 40 different pilotis width configurations. The Comfortable Wind Zone Ratio (CWZR) and Physiological Equivalent Temperature (PET) were used as primary evaluation metrics to systematically investigate the influence of varying inlet/outlet width ratios in building pilotis on the wind-thermal environment within courtyard-shaded zones. The results demonstrate that: (1) Under a fixed outlet size, enlarging the inlet significantly enhances the CWZR in the shaded area, with a 28.66% difference observed between inlet sizes of L/4 and L. In contrast, under a fixed inlet size, expanding the outlet has a negligible effect on CWZR improvement. (2) Under a fixed outlet size, increasing the inlet width substantially reduces PET in the shaded zone, showing a 2.46 °C difference between inlet sizes of L/4 and L. Conversely, under a fixed inlet size, widening the outlet has a minimal impact on PET reduction. (3) A negative correlation exists between CWZR and PET in the shaded area, indicating that an increase in CWZR leads to a decrease in PET values. The findings provide bioclimatically quantified guidelines for the spatial design of courtyard pilotis in hot-humid regions, offering practical insights for optimizing thermal comfort in shaded outdoor environments. Full article

This study examines the climate adaptability of traditional Hani ‘Mushroom Houses’ located in the rice terrace region of Honghe Hani Autonomous Prefecture, Yunnan, China. By analyzing 30 years of meteorological data, the study identifies the local climatic characteristics of high temperatures, high humidity, and significant diurnal temperature variations. The thermal comfort voting method was used to establish a quantitative relationship between the Physiological Equivalent Temperature (PET) index and residents’ subjective thermal perceptions, thereby assessing seasonal variations in thermal comfort. Field measurements of indoor and outdoor temperature, humidity, and wind speed were conducted in May and December 2023 to evaluate thermal interactions between rooms. This study demonstrated: (1) the critical roles of building orientation (e.g., northwest-facing design), functional layout (e.g., multi-story zoning), and structural forms (e.g., thick walls, thatched roofs) in regulating temperature and humidity. (2) Confirmed that Hani ‘Mushroom Houses’ stabilize indoor environments through passive strategies, including material selection (wood, rammed earth), natural ventilation (cross-draft design), and spatial organization (climate-buffering storage layers). (3) Provided empirical evidence for optimizing traditional dwellings (e.g., enhanced insulation, ventilation improvements) and advancing sustainable practices in similar climatic regions. Full article

Smart cities are widely regarded as a promising solution to urbanization challenges; however, environmental aspects such as outdoor thermal comfort and urban heat island are often less addressed than social and economic dimensions of sustainability. To address this gap, we developed and evaluated an affordable, scalable, and cost-effective weather station platform, consisting of a centralized server and portable edge devices to facilitate urban heat island and outdoor thermal comfort studies. This edge device is designed in accordance with the ISO 7726 (1998) standards and further enhanced with a positioning system. The device can regularly log parameters such as air temperature, relative humidity, globe temperature, wind speed, and geographical coordinates. Strategic selection of components allowed for a low-cost device that can perform data manipulation, pre-processing, store the data, and exchange data with a centralized server via the internet. The centralized server facilitates scalability, processing, storage, and live monitoring of data acquisition processes. The edge devices’ electrical and shielding design was evaluated against a commercial weather station, showing Mean Absolute Error and Root Mean Square Error values of 0.1 and 0.33, respectively, for air temperature. Further, empirical test campaigns were conducted under two scenarios: “stop-and-go” and “on-the-move”. These tests provided an insight into transition and response times required for urban heat island and thermal comfort studies, and evaluated the platform’s overall performance, validating it for nuanced human-scale thermal comfort, urban heat island, and bio-meteorological studies. Full article

With the intensification of climate challenges driven by rapid urbanization, the microclimate and thermal comfort of residential blocks have attracted increasing attention. Current research predominantly focuses on isolated morphological factors—such as building orientation, layout patterns, and height-to-width ratios—while neglecting the synergistic effects of multifactorial spatial configurations on outdoor thermal comfort. This study addresses this gap by analyzing 36 residential block samples in Wuhan, a representative city in a hot-summer and cold-winter (HSCW) region. Utilizing the Honeybee plugin in Grasshopper (GH) alongside the Universal Thermal Climate Index (UTCI), we simulate outdoor thermal environments to identify critical influencing elements. The results reveal how multifactor interactions shape thermal performance, providing evidence-based design strategies to optimize microclimate resilience in high-density urban contexts. This work advances the understanding of spatial morphology–thermal dynamics and offers practical insights for sustainable residential planning. This study systematically investigates the thermal performance of residential blocks through parametric prototyping and seasonal simulations. Sixteen morphological prototypes were developed by combining four building layout typologies (arrayed, staggered, enclosed, and hybrid) with three critical variables: the height-to-width ratio (HWR), building orientation deviation angle (θ), and sky visibility factor (SVF). Key findings reveal the following: (1) the hybrid layout demonstrates superior annual thermal adaptability when integrating fixed orientation (θ = 0°), moderate H/W = 1, and SVF = 0.4; (2) increased H/W ratios enhance thermal comfort levels across all layout configurations, particularly in winter wind protection; and (3) moderate orientation deviations (15° < θ < 30°) significantly improve microclimate performance in modular layouts by optimizing solar penetration and aerodynamic patterns. These evidence-based insights provide actionable guidelines for climate-responsive residential design in transitional climate zones, effectively balancing summer heat mitigation and winter cold prevention through spatial configuration optimization. Full article

Urban green spaces are crucial for regulating microclimates and enhancing human comfort. The study, conducted at Jiyang College of Zhejiang A&F University, investigates the effects of plant communities with diverse canopy structures on campus microclimates and thermal comfort in summer and winter. Data on air temperature (AT), relative humidity (RH), wind speed (WS), and light intensity (LI) were collected over three consecutive sunny days in both summer and winter. Concurrently, plant community structural characteristics, including three-dimensional green biomass (3DGB), canopy density (CD), and sky-view factor (SVF), were measured and analyzed. Quantitative relationships between these plant characteristics and microclimate/thermal comfort indices were evaluated using statistical analyses. The results indicate that, in summer, plant communities produced significant cooling (daily average AT reduced by 2.3 °C) and humidifying effects, and decreased the daily maximum thermal humidity index (THI) by 1 °C compared to control areas without vegetation. In winter, the moderation of temperature and humidity was present but less pronounced, and no statistically significant temperature difference was observed. Communities with larger 3DGB, higher CD, and lower SVF provided more effective shading and improved microclimatic regulation. A regression analysis identified AT as the primary factor influencing outdoor thermal comfort across both seasons. Planting configurations such as “Tree-Shrub-Herb” and “Tree-Small Tree”, as well as the use of broad-crowned shade trees, were shown to be effective in optimizing microclimate and outdoor comfort. Overall, enhancing the vegetation structure may address outdoor thermal comfort requirements in campus environments throughout the year. Full article

In recent years, China has continuously increased the construction of sports facilities, with the number and area of sports venues steadily growing. The use of more energy-efficient ventilation methods in gymnasiums has become one of the research hotspots. Taking a multi-functional gymnasium in Wuhan as an example, the gymnasium adopts a seat air supply device driven by natural wind to enhance indoor ventilation. This study uses the methods of field measurement and CFD simulation to analyze the application effect of this new type of natural ventilation device in hot summer and warm winter areas during the transition season. Through CFD simulation of the ventilation performance of the seat air supply at different opening rates, the indoor ventilation effect and thermal comfort were analyzed. The application of the seat air supply greatly improved the indoor environment and enhanced the comfort of personnel. After turning on the seat air supply, the maximum temperature difference between the indoors and outdoors increased from 1.7 °C to 3.4 °C, the natural air intake rate increased from approximately 50% to approximately 70%, the wind speed in the seat area significantly increased, the uniformity of the wind speed field in the movement area significantly increased, and the proportion of areas with low wind speed and no wind speed decreased to 9.6%. The proportion of areas with wind speeds ranging from 0.3 to 0.5 m/s increased from 8.8% to 33.0%. At 10:00 a.m., the temperature at the indoor station was relatively low. The opening of the seat air supply device reduced the PMV value of the front seats by an average of 0.39. When the indoor platform temperature reached the maximum value, the impact of equipment activation on the PMV index of the seat area was relatively small, with an average reduction of only 0.19. The research results show that the application of a natural wind-driven seat air supply in sports venues is very promising, providing a new idea for the energy-saving renovation of gymnasiums and effectively promoting the development of low-carbon undertakings. Full article