The Experts below are selected from a list of 1863 Experts worldwide ranked by ideXlab platform
Jan Carmeliet - One of the best experts on this subject based on the ideXlab platform.
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Modelling the Urban Microclimate and its Influence on Building Energy Demands of an Urban Neighbourhood
2020Co-Authors: Jonas Allegrini, Viktor Dorer, Jérôme Henri Kämpf, Jan CarmelietAbstract:In the past decades the portion of the population living in Urban areas has continuously increased. Due to the high building density, the Microclimate in Urban areas changed significantly compared to rural areas. The temperatures measured in Urban areas are, due to the Urban heat island (UHI) effect, higher compared to the rural temperatures. The UHI intensities are increasing with higher building densities and growing cities. Space cooling and heating demands of buildings are strongly affected by the local Microclimate at the building sites. Due to the climate change and the limited energy resources, energy saving and sustainability are nowadays important issues. A significant part of the global energy consumption is used for space cooling and space heating of buildings. Thus its minimization for buildings in Urban areas has great energy saving potential. Most building energy simulation (BES) models were developed for stand-alone buildings and therefore do not consider effects of the Urban Microclimate. This can lead to inaccurate predictions of the space cooling and heating demands for buildings in Urban areas. The aim of this paper is to investigate the Urban Microclimate and its potential influence on the energy demand of buildings in an Urban context by conducting detailed flow, radiation and building energy simulations at the Urban neighborhood scale. CitySim is used for the radiation and building energy simulations. In CitySim detailed radiation models for solar and longwave radiation are implemented that can account for the radiation exchange between neighbouring buildings. The flow around the buildings is modelled by running CFD (computational fluid dynamics) simulations using OpenFOAM. As a result it is shown, how the temperatures and wind speeds can strongly differ within different Urban areas. Further an approach is presented, to consider the local Microclimate in the building energy simulation tool CitySim.
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coupling of physical phenomena in Urban Microclimate a model integrating air flow wind driven rain radiation and transport in building materials
urban climate, 2017Co-Authors: Jan Carmeliet, A Kubilay, Dominique DeromeAbstract:Abstract Building materials play an important role in the absorption, transport and storage of heat and moisture in the built environment. A fully-integrated Urban Microclimate model is proposed, which solves for wind flow and for the transport of heat and moisture in the air and building materials. The model includes long-wave and short-wave radiative exchange between surfaces and the distribution of wind-driven rain intensity. Transport in air and building materials are coupled in such a way that the steady Reynolds-averaged Navier-Stokes (RANS) is solved iteratively with the unsteady heat and moisture transfer in building materials. The proposed approach provides the information required for analyzing different contributions of convective cooling, sensible heat transfer due to rain, evaporation, in addition to the thermal storage throughout the day. This approach is demonstrated with a case study investigating the impact of rain deposition on an isolated three-dimensional street canyon lined with porous building materials. The study shows different rate of evaporation and duration of evaporative cooling for a change in wind speed during a rain event. The distribution of wind-driven rain particularly influences the spatial and temporal distribution of surface and air temperatures. A significant influence of neighboring surfaces is found on the surface temperatures.
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influence of morphologies on the Microclimate in Urban neighbourhoods
Journal of Wind Engineering and Industrial Aerodynamics, 2015Co-Authors: Jonas Allegrini, Viktor Dorer, Jan CarmelietAbstract:Abstract In the past decades the portion of the population living in Urban areas has continuously increased. Due to the high building density, the Microclimate in Urban areas changes significantly compared to rural areas. The temperatures measured in Urban areas are higher compared to the rural temperatures due to the Urban heat island (UHI) effect. Furthermore, the longwave and solar radiation exchanges are influenced by shadowing, reflections between buildings and reduced sky view factors. The local Urban Microclimate has an influence on the energy demand of buildings and on human comfort and health in Urban areas. In summer the human comfort in Urban areas can decrease due to higher air and surface temperatures and lower wind speeds compared to rural areas. The local Urban Microclimate is difficult to predict because of the complex interaction of physical phenomena across a large range of time and length scales. Few guidelines exist for architects to mitigate UHI effects or its impacts. The aim of this paper is to model the Urban Microclimate with CFD and building energy simulations and to investigate in detail the influence of different Urban building morphologies on the Urban Microclimate. This approach and the results of this study can be used to find measures to mitigate the UHI effect. The results show that building facade surface temperatures are mainly influenced by the distance between buildings. For Urban morphologies with similar surface temperatures, the air temperatures can still strongly vary due to different wind flow patterns causing different rates of removing heat by wind.
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Urban energy and Microclimate: Wind tunnel experiments and multiscale modeling
Proceedings of BS 2013: 13th Conference of the International Building Performance Simulation Association, 2013Co-Authors: Jan Carmeliet, Jonas Allegrini, Samar Saneinejad, Peter Moonen, Viktor DorerAbstract:An Urban Microclimate model including air flow, heat and moisture transport in porous Urban surfaces and solar and longwave radiation is presented, validated with wind tunnel experiments and used to study the effect of evaporative cooling on the thermal comfort in a street canyon. Copyright ? 2011 by IPAC'11/EPS-AG.
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modelling the Urban Microclimate and its impact on the energy demand of buildings and building clusters
Proceedings of BS2013: 13th Conference of International Building Performance Simulation Association Chambéry France August 26-28, 2013Co-Authors: Viktor Dorer, Jonas Allegrini, Peter Moonen, Jérôme Henri Kämpf, Kristina Orehounig, Govinda Upadhyay, Jan CarmelietAbstract:The Urban Microclimate (UMC) can strongly affect the building energy demand. In this paper, the impact of the UMC on the space heating and cooling energy demand of buildings is analysed for typical office buildings in street canyon configurations, using detailed building energy simulations (BES). Convective aspects of the UMC are modelled using computational fluid dynamics (CFD) and data are transferred to BES, either by convective heat transfer coefficients or by directly coupling CFD and BES. Measured Urban heat island intensities are additionally considered. Comparisons to stand-alone buildings show the large influence of the Urban situation. We then outline multi-scale modelling concepts to consider UMC effects at larger Urban scales, using a city energy simulation model and an adapted UMC model.
Bje Bert Blocken - One of the best experts on this subject based on the ideXlab platform.
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cfd simulation of Urban Microclimate validation using high resolution field measurements
Science of The Total Environment, 2019Co-Authors: Bje Bert Blocken, H Montazeri, Nestoras N Antoniou, Marina NeophytouAbstract:Heat stress in Urban areas can have detrimental effects on human health, comfort and productivity. In order to mitigate heat stress, Computational Fluid Dynamics (CFD) simulations of Urban Microclimate are increasingly used. The validation of these simulations however requires high-quality experimental data to be compared with the simulation results. Due to lack of available high-resolution high-quality experimental data, CFD validation of Urban Microclimate for real Urban areas is normally performed based on either a limited number of parameters measured at a limited number of points in space, or on experiments for idealized generic configurations. In this study, CFD simulations of Urban Microclimate are performed for a dense highly heterogeneous district in Nicosia, Cyprus and validated using a high-resolution dataset of on-site measurements of air temperature, wind speed and surface temperature conducted for the same district area. The CFD simulations are performed based on the 3D Unsteady Reynolds-Averaged Navier-Stokes (URANS) equations and the simulated period covers four consecutive days in July 2010. It is shown that the CFD simulations can predict air temperatures with an average absolute difference of 1.35 °C, wind speed with an average absolute difference of 0.57 m/s and surface temperatures with an average absolute difference of 2.31 °C. Based on the comparative results, conclusions are made regarding the performance of URANS for the selected application and possible reasons for deviations between measured and simulated results are discussed.
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impact of Urban Microclimate on summertime building cooling demand a parametric analysis for antwerp belgium
Applied Energy, 2018Co-Authors: Yasin Toparlar, Bje Bert Blocken, Bino Maiheu, G J F Van HeijstAbstract:Meteorological measurements are conducted in Antwerp, Belgium in July 2013, followed by CFD Urban Microclimate simulations considering the same city and time period. The simulations are found to be able to reproduce measured air temperatures inside central Antwerp with an average absolute difference of 0.88 °C. The simulation results supplemented with measurements are used to generate location-specific Microclimatic Conditions (MCs) in three locations: (1) a rural location outside Antwerp; (2) an Urban location inside Antwerp, away from an Urban park; and (3) another Urban location, close to the same park. Building Energy Simulations (BES) are performed for 36 cases based on three different MCs, two building use types and six sets of construction characteristics, ranging from pre-1946 buildings to new, low-energy buildings. Monthly Cooling Demands (CDs) are extracted for each case and compared with each other. The results demonstrate that compared to the air temperatures in the rural area, on average, air temperatures at the Urban sites away and close to the park are 3.3 °C and 2.4 °C higher, respectively. This leads to an additional monthly CD of up to 90%. CDs of buildings with better thermal insulation and lower infiltration rates can increase by 48% once moved from the rural location to an Urban location, which may lead to the reconsideration of design guidelines of low-energy buildings exposed to an Urban MC. Although the proximity of an Urban park cannot fully compensate the increased CD by an Urban MC, residential buildings close to the park are found to have on average 13.9% less CD during July 2013, compared with buildings away from the same park. The influence of the Urban park on the CDs of buildings in its vicinity is strongly linked to the meteorological wind direction. Professionals focusing on energy-efficient buildings in cities are advised to conduct energy predictions with location-specific MC data, instead of only using city-averaged meteorological data.
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CFD Simulations and on-site measurements of Urban Microclimate in a real compact Urban area
2018Co-Authors: Nestoras N Antoniou, Marina Neophytou, H Hamid Montazeri, Bje Bert BlockenAbstract:The Urban population has reached the highest number ever recorded. Based on recent studies, this number is going to increase even further, with strong consequences for the Urban Microclimate. In this perspective, the analysis of microclimatic conditions in the Urban environment is getting more significant. This study analyzes microclimatic conditions in a real Urban area. The real compact inhomogeneous Urban area under study is located in Nicosia old town, in Cyprus. High-resolution Computational Fluid Dynamics (CFD) simulations are performed based on the 3D unsteady Reynolds-Averaged Navier-Stokes equations to assess the air temperature, surface temperatures and wind speed distributions. The CFD results are compared with on-site measurements for the same area. The results show that CFD can predict air temperatures in compact real Urban areas, with an average deviation of approximately 7%. Based on the results, conclusions are going to be made regarding microclimatic conditions in the case study area.
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a review on the cfd analysis of Urban Microclimate
Renewable & Sustainable Energy Reviews, 2017Co-Authors: Yasin Toparlar, Bje Bert Blocken, Bino Maiheu, G J F Van HeijstAbstract:Urban Microclimate studies are gaining popularity due to rapid Urbanization. Many studies documented that Urban Microclimate can affect building energy performance, human morbidity and mortality and thermal comfort. Historically, Urban Microclimate studies were conducted with observational methods such as field measurements. In the last decades, with the advances in computational resources, numerical simulation approaches have become increasingly popular. Nowadays, especially simulations with Computational Fluid Dynamics (CFD) is frequently used to assess Urban Microclimate. CFD can resolve the transfer of heat and mass and their interaction with individual obstacles such as buildings. Considering the rapid increase in CFD studies of Urban Microclimate, this paper provides a review of research reported in journal publications on this topic till the end of 2015. The studies are categorized based on the following characteristics: morphology of the Urban area (generic versus real) and methodology (with or without validation study). In addition, the studies are categorized by specifying the considered Urban settings/locations, simulation equations and models, target parameters and keywords. This review documents the increasing popularity of the research area over the years. Based on the data obtained concerning the Urban location, target parameters and keywords, the historical development of the studies is discussed and future perspectives are provided. According to the results, early CFD Microclimate studies were conducted for model development and later studies considered CFD approach as a predictive methodology. Later, with the established simulation setups, research efforts shifted to case studies. Recently, an increasing amount of studies focus on Urban scale adaptation measures. The review hints a possible change in this trend as the results from CFD simulations can be linked up with different aspects (e.g. economy) and with different scales (e.g. buildings), and thus, CFD can play an important role in transferring Urban climate knowledge into engineering and design practice.
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cfd simulation and validation of Urban Microclimate a case study for bergpolder zuid rotterdam
Building and Environment, 2015Co-Authors: Yasin Toparlar, Bje Bert Blocken, Van Gjf Gertjan Heijst, W Wendy D Janssen, Van Taj Twan Hooff, H Montazeri, Hjp Harry TimmermansAbstract:Considering climate change and the rapid trend towards Urbanization, the analysis of Urban Microclimate is gaining importance. The Urban Heat Island (UHI) effect and summer-time heat waves can significantly affect Urban Microclimate with negative consequences for human mortality and morbidity and building energy demand. So far, most studies on Urban Microclimate employed observational approaches with field measurements. However, in order to provide more information towards the design of climate adaptive Urban areas, deterministic analyses are required. In this study, Computational Fluid Dynamics (CFD) simulations are performed to predict Urban temperatures in the Bergpolder Zuid region in Rotterdam, which is planned to be renovated to increase its climate resilience. 3D unsteady Reynolds-averaged Navier–Stokes (URANS) simulations with the realizable k–e turbulence model are performed on a high-resolution computational grid. The simulations include wind flow and heat transfer by conduction, convection and radiation. The resulting surface temperatures are validated using experimental data from high-resolution thermal infrared satellite imagery performed during the heat wave of July 2006. The results show that the CFD simulations are able to predict Urban surface temperatures with an average deviation of 7.9% from the experimental data. It is concluded that CFD has the potential of accurately predicting Urban Microclimate. Results from CFD simulations can therefore be used to identify problem areas and to evaluate the effect of climate adaptation measures in these areas such as Urban greening and evaporative cooling.
Yasin Toparlar - One of the best experts on this subject based on the ideXlab platform.
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impact of Urban Microclimate on summertime building cooling demand a parametric analysis for antwerp belgium
Applied Energy, 2018Co-Authors: Yasin Toparlar, Bje Bert Blocken, Bino Maiheu, G J F Van HeijstAbstract:Meteorological measurements are conducted in Antwerp, Belgium in July 2013, followed by CFD Urban Microclimate simulations considering the same city and time period. The simulations are found to be able to reproduce measured air temperatures inside central Antwerp with an average absolute difference of 0.88 °C. The simulation results supplemented with measurements are used to generate location-specific Microclimatic Conditions (MCs) in three locations: (1) a rural location outside Antwerp; (2) an Urban location inside Antwerp, away from an Urban park; and (3) another Urban location, close to the same park. Building Energy Simulations (BES) are performed for 36 cases based on three different MCs, two building use types and six sets of construction characteristics, ranging from pre-1946 buildings to new, low-energy buildings. Monthly Cooling Demands (CDs) are extracted for each case and compared with each other. The results demonstrate that compared to the air temperatures in the rural area, on average, air temperatures at the Urban sites away and close to the park are 3.3 °C and 2.4 °C higher, respectively. This leads to an additional monthly CD of up to 90%. CDs of buildings with better thermal insulation and lower infiltration rates can increase by 48% once moved from the rural location to an Urban location, which may lead to the reconsideration of design guidelines of low-energy buildings exposed to an Urban MC. Although the proximity of an Urban park cannot fully compensate the increased CD by an Urban MC, residential buildings close to the park are found to have on average 13.9% less CD during July 2013, compared with buildings away from the same park. The influence of the Urban park on the CDs of buildings in its vicinity is strongly linked to the meteorological wind direction. Professionals focusing on energy-efficient buildings in cities are advised to conduct energy predictions with location-specific MC data, instead of only using city-averaged meteorological data.
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a review on the cfd analysis of Urban Microclimate
Renewable & Sustainable Energy Reviews, 2017Co-Authors: Yasin Toparlar, Bje Bert Blocken, Bino Maiheu, G J F Van HeijstAbstract:Urban Microclimate studies are gaining popularity due to rapid Urbanization. Many studies documented that Urban Microclimate can affect building energy performance, human morbidity and mortality and thermal comfort. Historically, Urban Microclimate studies were conducted with observational methods such as field measurements. In the last decades, with the advances in computational resources, numerical simulation approaches have become increasingly popular. Nowadays, especially simulations with Computational Fluid Dynamics (CFD) is frequently used to assess Urban Microclimate. CFD can resolve the transfer of heat and mass and their interaction with individual obstacles such as buildings. Considering the rapid increase in CFD studies of Urban Microclimate, this paper provides a review of research reported in journal publications on this topic till the end of 2015. The studies are categorized based on the following characteristics: morphology of the Urban area (generic versus real) and methodology (with or without validation study). In addition, the studies are categorized by specifying the considered Urban settings/locations, simulation equations and models, target parameters and keywords. This review documents the increasing popularity of the research area over the years. Based on the data obtained concerning the Urban location, target parameters and keywords, the historical development of the studies is discussed and future perspectives are provided. According to the results, early CFD Microclimate studies were conducted for model development and later studies considered CFD approach as a predictive methodology. Later, with the established simulation setups, research efforts shifted to case studies. Recently, an increasing amount of studies focus on Urban scale adaptation measures. The review hints a possible change in this trend as the results from CFD simulations can be linked up with different aspects (e.g. economy) and with different scales (e.g. buildings), and thus, CFD can play an important role in transferring Urban climate knowledge into engineering and design practice.
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cfd simulation and validation of Urban Microclimate a case study for bergpolder zuid rotterdam
Building and Environment, 2015Co-Authors: Yasin Toparlar, Bje Bert Blocken, Van Gjf Gertjan Heijst, W Wendy D Janssen, Van Taj Twan Hooff, H Montazeri, Hjp Harry TimmermansAbstract:Considering climate change and the rapid trend towards Urbanization, the analysis of Urban Microclimate is gaining importance. The Urban Heat Island (UHI) effect and summer-time heat waves can significantly affect Urban Microclimate with negative consequences for human mortality and morbidity and building energy demand. So far, most studies on Urban Microclimate employed observational approaches with field measurements. However, in order to provide more information towards the design of climate adaptive Urban areas, deterministic analyses are required. In this study, Computational Fluid Dynamics (CFD) simulations are performed to predict Urban temperatures in the Bergpolder Zuid region in Rotterdam, which is planned to be renovated to increase its climate resilience. 3D unsteady Reynolds-averaged Navier–Stokes (URANS) simulations with the realizable k–e turbulence model are performed on a high-resolution computational grid. The simulations include wind flow and heat transfer by conduction, convection and radiation. The resulting surface temperatures are validated using experimental data from high-resolution thermal infrared satellite imagery performed during the heat wave of July 2006. The results show that the CFD simulations are able to predict Urban surface temperatures with an average deviation of 7.9% from the experimental data. It is concluded that CFD has the potential of accurately predicting Urban Microclimate. Results from CFD simulations can therefore be used to identify problem areas and to evaluate the effect of climate adaptation measures in these areas such as Urban greening and evaporative cooling.
Ariane Middel - One of the best experts on this subject based on the ideXlab platform.
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sensor lag correction for mobile Urban Microclimate measurements
urban climate, 2015Co-Authors: Benjamin L. Ruddell, Ariane MiddelAbstract:Abstract Some uncertainty in mobile Microclimate observations stems from sensor lags. This is especially critical in mobile transect campaigns conducted in Urban areas, where observations have to be related to the quickly varying complex surroundings of the sensor, which becomes difficult if the sensor has a high time constant relative to environmental scale and sensor velocity. We present an optimized method for sensor lag correction using a transfer function, based on the optimization of three correction parameters: moving average window size, transfer function setup, and linear time shift. We evaluate the method by comparing the corrected temperatures measured with “slow” Resistance Temperature Detectors (RTD) to a ground truth provided by synchronous measurements with thermocouples that have a time constant of less than one second. Theoretical assumptions about the correction procedure design are substantiated by the optimization procedure, which yields consistent results for mobile transect data sets recorded at different times of day and in different seasons.
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TraVis - A visualization framework for mobile transect data sets in an Urban Microclimate context
2015 IEEE Pacific Visualization Symposium (PacificVis), 2015Co-Authors: Ariane Middel, Benjamin L. Ruddell, Hans HagenAbstract:In Urban Microclimate research, mobile transects are utilized to observe the relationship between atmospheric variables and the Urban environment. However, the data sets resulting from mobile measurements are complex: They are spatially dependent, multivariate, and often-times multitemporal. At the same time, the spatial context of each observation - its field of view and area represented - is physically complex and dynamic. These properties make analysis and visualization challenging. We present a prototype visualization framework that assists researchers in the analysis of mobile transect measurements. The system enables users to visualize and explore observations as walls that delineate the transect route on a map. The observed attributes are stacked upon each other within these walls as ribbons to facilitate the qualitative analysis of spatial variability and multivariate correlations. The relationship between observations and spatial context can interactively be explored by moving a slider along the transect route. For each observation on the track, the spatially contextual source area is displayed and linked to a view of the fraction of land cover classes contained within the source area. These qualitative analysis capabilities are complemented by an interactive clustering interface, which allows for the classification of transect segments according to a coherent pattern of multivariate relationships between a user-defined set of observations. The framework was developed by a team comprising both visualization and Urban Microclimate researchers, and a case study shows its utility for this specialized application.
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PacificVis - TraVis - A visualization framework for mobile transect data sets in an Urban Microclimate context
2015 IEEE Pacific Visualization Symposium (PacificVis), 2015Co-Authors: Ariane Middel, Benjamin L. Ruddell, Hans HagenAbstract:In Urban Microclimate research, mobile transects are utilized to observe the relationship between atmospheric variables and the Urban environment. However, the data sets resulting from mobile measurements are complex: They are spatially dependent, multivariate, and often-times multitemporal. At the same time, the spatial context of each observation - its field of view and area represented - is physically complex and dynamic. These properties make analysis and visualization challenging. We present a prototype visualization framework that assists researchers in the analysis of mobile transect measurements. The system enables users to visualize and explore observations as walls that delineate the transect route on a map. The observed attributes are stacked upon each other within these walls as ribbons to facilitate the qualitative analysis of spatial variability and multivariate correlations. The relationship between observations and spatial context can interactively be explored by moving a slider along the transect route. For each observation on the track, the spatially contextual source area is displayed and linked to a view of the fraction of land cover classes contained within the source area. These qualitative analysis capabilities are complemented by an interactive clustering interface, which allows for the classification of transect segments according to a coherent pattern of multivariate relationships between a user-defined set of observations. The framework was developed by a team comprising both visualization and Urban Microclimate researchers, and a case study shows its utility for this specialized application.
Ardeshir Mahdavi - One of the best experts on this subject based on the ideXlab platform.
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Methodologies for UHI Analysis
Counteracting Urban Heat Island Effects in a Global Climate Change Scenario, 2020Co-Authors: Ardeshir Mahdavi, Kristina Kiesel, Milena VuckovicAbstract:A central strand of research work in the realm of Urban physics aims at a better understanding of the variance in microclimatic conditions due to factors such as building agglomeration density, anthropogenic heat production, traffic intensity, presence and extent of green areas and bodies of water. The characteristics and evolution of the Urban Microclimate is not only relevant to people’s experience of outdoor thermal conditions in the cities. Higher air temperatures also exacerbate discomfort caused by the overheating of indoor spaces and increases cooling energy expenditures. It can be argued that the solid understanding of the temporal and spatial variance of Urban Microclimate represents a prerequisite for the reliable assessment of the thermal performance of buildings (energy requirements, indoor thermal conditions). In this context, the present treatment entails a three-fold contribution. First, the existence and extent of the UHI phenomena are documented for a number of Central-European cities. Second, a comprehensive assessment of the effectiveness of UHI mitigation measures in these cities is described that is conducted using advanced numeric modelling instruments. Third, a systematic framework is proposed to identify a number of variables of the Urban environment that are hypothesized to influence UHI and the Urban Microclimate variance. These variables pertain to both geometric (morphological) and semantic (material-related) Urban features.
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toward advanced representations of the Urban Microclimate in building performance simulation
Sustainable Cities and Society, 2016Co-Authors: Milena Vuckovic, Kristina Kiesel, Ardeshir MahdaviAbstract:Abstract The present contribution is concerned with the potential of empirically-based methods to capture the Microclimate variance across a city and its implications for the performance of buildings. We explore the possibility to explain microclimatic variance across an Urban area based on geometric and semantic attributes of specific locations. We use high-resolution and dynamic weather data streams across numerous Urban locations in the city of Vienna, Austria. Using advanced data extraction methods, the values of a number of Urban attributes that are hypothesized to contribute to the Urban Microclimate variance (e.g. morphological factors, semantic properties of Urban surfaces) are derived for these locations. The results point to possible correlations between location-based climatic conditions and distinct Urban attributes that could be harnessed to formulate empirically-based algorithms for generating customized microclimatic boundary conditions.
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toward advanced representations of the Urban Microclimate in building performance simulation
Energy Procedia, 2015Co-Authors: Milena Vuckovic, Kristina Kiesel, Ardeshir MahdaviAbstract:Abstract The present paper is concerned with the potential of empirically-based methods to capture the Microclimate variance across a city and its implications for the performance of buildings. We explore the possibility to explain microclimatic variance across an Urban area based on geometric and semantic attributes of specific locations. We use high-resolution and dynamic weather data streams across numerous Urban locations in the city of Vienna, Austria. Using advanced data extraction methods, the values of a number of Urban attributes that are hypothesized to contribute to the Urban Microclimate variance (e.g. morphological factors, semantic properties of Urban surfaces) are derived for these locations. The results point to the likelihood that correlations between location-based climatic conditions and distinct Urban attributes exist and could be potentially harnessed to formulate empirically- based algorithms for generating customized microclimatic boundary conditions.
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Empirical and computational assessment of the Urban Heat Island phenomenon and related mitigation measures
Geographia Polonica, 2014Co-Authors: Ardeshir Mahdavi, Kristina Kiesel, Milena VuckovicAbstract:A central strand of research work in the realm of Urban physics aims at a better understanding of the variance in microclimatic conditions due to factors such as building agglomeration density, anthropogenic heat production, traffic intensity, presence and extent of green areas and bodies of water, etc. This research has been motivated in part by phenomena associated with climate change and Urban heat islands (UHI) and their implications for the Urban Microclimate. Note that the characteristics and evolution of the Urban Microclimate is not only relevant to people’s experience of outdoor thermal conditions in the cities. It can be argued that the solid understanding of the temporal and spatial variance of Urban Microclimate represents a prerequisite for the reliable assessment of the thermal performance of buildings (energy requirements, indoor thermal conditions). In this context, the present paper entails a three-fold contribution. First, the existence and extent of the UHI phenomena are documented for a number of Central-European cities. Second, a number of variables of the Urban environment are identified that are hypothesized to influence UHI and the Urban Microclimate variance. These variables, which pertain to both geometric (morphological) and semantic (material-related) Urban features are captured within a formal and systematic framework. Third, to support the process of design and evaluation of UHI mitigation measures, the potential of both numerical (simulation-based) applications and empirically-based Urban Microclimate models are explored.
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ICT-EurAsia - Empirical and Computational Issues of Microclimate Simulation
Information and Communication Technology, 2014Co-Authors: Aida Maleki, Milena Vuckovic, Kristina Kiesel, Ardeshir MahdaviAbstract:The dynamic variability of weather conditions and complex geometry and semantics of Urban domain impose significant constraints on the empirical study of Urban Microclimate. Thus, numerical modeling is being increasingly deployed to capture the very dynamics of Urban Microclimate. In this context, the present paper illustrates the basic processes of calibrating and preparing a numerical model for the simulation of the Urban Microclimate.
