Design choices and comfort outdoor in sustainable neighborhoods

2016

This research has tested the effects on the urban microclimate of the transformations induced in the outdoor urban spaces and, in parallel, how these modifications effect the reduction of temperature in the confined indoor spaces of the built environments. Open spaces and the surface of urban volumes are considered, measured and evaluated as a unique interacting environment. The volumetric configuration of the urban textures and the materials that constitute the external surfaces, are the main factors that influence the microclimate of a city. Comprehend and being able to transform in an adequate way the urban settings could contribute to the improvement of the thermal comfort in outdoor and indoor built environments. By using as a principal indicator thermal comfort the variation of the external temperatures in an unprecedented collaboration between different scales and different environmental simulation systems, this paper analyses the energy saving potential given by the use of green and passive techniques and shows the synergies that may arise between outdoor and indoor spaces. Volumetric configuration, urban microclimate, thermal comfort, environmental simulation systems, green and passive techniques

2011

Urban planners and designers often consider the comfort conditions indoors while neglecting the same in the outdoor urban spaces. In particular, the outdoor comfort conditions in the developing countries are generally unnoticed, and the most affected are the urban poor who spend most of their time outdoors. Therefore, this paper aims at the enhancement of outdoor thermal comfort conditions, through the analysis of urban built form and climate parameters in Chennai Metropolitan Area, India. The study examines the thermal comfort conditions of six urban built forms (dense compact mid-rise urban form and dispersed low-rise urban form) in relation to urban geometry (the density of buildings, height to width ratio), sky view factor (SVF) and green cover (vegetation), using RayMan a computer model used to model the radiation fluxes in simple and complex urban environments. The comfort conditions of the outdoor urban spaces are analyzed in terms of air temperature and Physiologically Equiv...

MSA Engineering Journal

The research has studied the relationship between the quality of thermal comfort in the outdoor spaces of the residential urban clusters on the quality of thermal comfort in the indoor spaces in order to provide a proposed approach for the designs of the outdoor spaces that work to raise the thermal comfort efficiency of the indoor spaces overlooking them, by studying the extent of the impact of these design variables on the thermal comfort in the outdoor urban space , by measuring the predictive average value of PMV as an indicator of outdoor thermal comfort, that is by using the results of previous studies to measure the thermal comfort of the external spaces of buildings through the inputs of climatic determinants and urban variables such as the geometric shape and orientation of the building block with the fixation of the other influential urban factors, by conducting a simulation using ENVI-MET for the outdoor spaces of the commonly designed residential urban clusters in the New Cairo area, and measuring the value of PMV as an indicator of the thermal comfort value of the indoor spaces, using DESIGN BUILDER for the indoor spaces, then comparing the results of the thermal comfort.

The outdoor conditioning is an important research field, especially in the context of sustainable urban development. This paper aims to understand the influence of built environment in microclimatic variations of the open spaces in the city center of Athens, with the intention to identify design strategies for future urban designers which can improve comfort in the outdoor living environment.

Prostor

In this study, academic staff residential buildings were studied as part of a university campus located in a hot and humid climate zone in Türkiye. Within the scope of the study, the energy efficient architectural and landscape design decisions of the buildings built in 1976 were examined. The aim was to determine the energy performance of buildings built about 50 years ago and to quantify the effect of changing landscape conditions on thermal comfort. In this aim, the outdoor thermal comfort level was determined by creating microclimate simulations for the hottest day and time of the year. Microclimatic analyses were performed with ENVI-met software and thermal comfort was evaluated with two metrics, average PMV and ASHRAE scale. The energy performance of the buildings was determined using ecological design parameters. An approach to global environmental problems is the use of ecological design principles, including architectural and landscape design principles. It is important to ...

E3S Web of Conferences

Outdoor spaces in cities contribute to improve urban quality. Improving outdoor thermal comfort is important to consider in achieving urban life and functionality. In order, green areas have shown to be effective at reducing the effects of several climatic elements associated with heat stress in urban settings while also giving people a great outdoor setting. The most basic problem is that most recent projects in Constantine cities did not take into account the usage of green design solutions, causing in human outdoor heat discomfort. This study aims to enable designers to ameliorate the conditions in outdoor spaces. The main objective of this paper is to discuss and assess the impact of geometry and shade trees on the external thermal comfort conditions due to the significant effects of thermal comfort on citizens, especially in hot and dry regions. The methodology is based on in-situ measurements and a questionnaire survey during the warm season. A simulation with Envi-met5 softwa...

International Journal of Heat and Technology, 2022

Improving outdoor thermal comfort of the urban spaces is one of the most important challenges that cities have to carry out in the next years. The aim of this work consists of assessing the impact of urban variables and to quantify the influence of greening on outdoor thermal comfort conditions. The work compares six neighborhoods in the city of Turin characterized by different urban forms, contexts, and green areas. External thermal comfort conditions were measured by evaluating a series of indicators with the support of the ENVI-met tool. Through the analysis of various scenarios, outdoor thermal comfort conditions were measured using green mitigation measures, like vegetated areas, trees, and green roofs. The results allow the evaluation on how outdoor thermal comfort varies in relation to urban form and greenery. By comparing neighborhoods with different urban characteristics, it was possible to define the most effective form for the city of Turin. Higher levels of mean radiant temperature were obtained with open form neighborhoods with a prevalent East-West orientation, a low buildings' density, and a low height-to-width ratio. However, thermal comfort conditions can be mitigated by court-form districts and the presence of greenery, to increase the livability of the urban outdoor environment.

Sustainable Development and Planning VI, 2013

Microclimate conditions in urban open spaces are directly linked to the configuration of street axes and building heights and their attributes. Within street canyons, public places, and open spaces, the local microclimate depends directly on the physical properties of the surrounding surfaces and objects, producing well-known effects that can decrease or increase thermal loads. All of these phenomena can greatly influence the comfort of a city and the thermal comfort of pedestrians. Thermal comfort is an indicator that cannot be easily converted into physical parameters. However, it may be defined more qualitatively as the range of climatic conditions in which most people feel comfortable. One well-recognized thermal comfort index used to measure comfort levels inside a space is the predicted mean vote (PMV). Fanger's PMV index has been widely used in the last ten years. It is based on six factors: air temperature, air speed, humidity, mean radiant temperature, metabolic rate, and clothing levels. The comfort equation establishes relationships among the abovementioned environmental variables, clothing type, and metabolic rate. The authors present results of PMV simulations using a multi-objective optimization tool (i.e., modeFrontier). ModeFRONTIER is an integration platform used to optimize and arrange PMV algorithms linked to urban geometry parameters (e.g., the height-to-width (H/W) ratio of urban streets). The optimization process employs given constraints, custom procedural algorithms, and genetic algorithms to examine a wide urban space and identify interesting relationships among the variables considered. Urban geometry, meteorological data, and latent influences are examined and negotiated quantitatively to improve outdoor thermal comfort.

Sustainability

One of the most important issues in urban studies relating to climate and environmental sustainability is the analysis of the thermal conditions of urban public spaces, especially urban streets, since this issue seems to affect the comfort of citizens using such spaces. Thus, the main aim of the present study is to investigate the effect of streetscape parameters on the thermal comfort of citizens using urban streets in a hot summer and in a hot semi-arid climate. For this purpose, Karimkhan-e-Zand Street in Shiraz, Iran, was selected as the case study. The selected street is a historical and popular public space of Shiraz. In the present study, using physical and micro-climatic data analyzed in ENVI-met v4 software, the thermal comfort conditions of Karimkhan-e-Zand in Shiraz on 10 July were simulated during the hottest day of the year. Furthermore, the relationships between physical street parameters and micro-climatic parameters and their effects on the thermal comfort index (PMV...

The Sustainable City IX, 2014

Urban climate conditions affect how cities will develop in the future, not only because of the impact on the environment or on the energy consumption of buildings, but also on outdoor human comfort. The configuration of buildings is one of the main factors that influence the different microclimates in the city. Understanding and especially being able to predict and manipulate these urban microclimates may help improve different aspects of urban life including the outdoor thermal comfort. Because of this, it is possible to use indices of outdoor thermal conform to understand when and how the configurations of building affect the microclimate conditions. This paper describes a method that; (i) enables the integration of microclimate data into the creation of new urban forms using outdoor thermal comfort as an indicator, and (ii) translates this knowledge into a parameterized design-feedback tool. In this way, it will be possible to support the design process by automated tools that explore design spaces of urban forms according to measurements and empirical findings on the relationship between microclimate data and the building geometries.