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Two office layouts with high and low levels of thermal control were compared, respectively traditional cellular and contemporary open plan offices. The traditional Norwegian practice provided every user with control over a window, blinds, door, and the ability to adjust heating and cooling. Occupants were expected to control their thermal environment to find their own comfort, while air conditioning was operating in the background to ensure the indoor air quality. In contrast, in the British open plan office, limited thermal control was provided through openable windows and blinds only for occupants seated around the perimeter of the building. Centrally operated displacement ventilation was the main thermal control system. Users’ perception of thermal environment was recorded through survey questionnaires, empirical building performance through environmental measurements and thermal control through semi-structured interviews. The Norwegian office had 35% higher user satisfaction and 20% higher user comfort compared to the British open plan office. However, the energy consumption in the British practice was within the benchmark and much lower than the Norwegian office. Overall, a balance between thermal comfort and energy efficiency is required, as either extreme poses difficulties for the other. [ABSTRACT FROM AUTHOR]

The most significant threat that mankind faces in the 21th century is global warming. Buildings, which account for 40% of global energy consumption and greenhouse gas emissions, play a pivotal role in global warming. Estimates show that their destructive impact will grow by 1.8% per year through 2050, which indicates that future consumption and emissions will be worse than today. Therefore, the impact of cooling systems cannot be ignored, as they, along with ventilation and heating systems, account for 60% of the energy consumed in buildings. Passive cooling techniques are a promising alternative to conventional cooling systems. Of the various passive cooling strategies, thermal energy storage by means of latent heat is an efficient way to increase the thermal inertia of building envelopes, which would reduce temperature fluctuations, leading to the improved thermal comfort of occupants. Phase change materials (PCMs) with high density for thermal energy storage can be efficiently employed to this purpose. This paper reviews recent studies of the application of PCMs for passive cooling in buildings. From the literature, a comprehensive list of different organic, inorganic and eutectic PCMs appropriate for passive cooling in buildings are reviewed. Full-scale testing and numerical modeling were found to be the most popular investigative methods used for experimental and theoretical analysis of PCMs. The combination of these two methods can provide a detailed and valid technique for PCM investigations. Finally, incorporating PCMs into building walls with macro encapsulation was also a dominant interest in previous studies. [ABSTRACT FROM AUTHOR]

Urban heat island (UHI) effects were first observed in London in the 19th century. The urban heat island is identified by developing higher temperatures in urban areas than the surrounding rural areas that directly surround them. However, there are some main mitigation strategies to deal with subtropical UHI, such as increasing the albedo of the urban environment (reflective pavement) and developing the green infrastructure (green roof) in urban areas. This study would analyse the microclimate in a subtropical city by evaluating meteorological parameters with a three-dimensional model simulation software of computational fluid dynamics (CFD) named ENVI-Met. To evaluate Urban Heat Island mitigation strategies for a Subtropical City Centre, subtropical city Osaka, Japan, is selected to investigate UHI with modelling. The simulation has been used to applicate the five scenarios (base scenario, cool pavement scenario, cool roof scenario, increasing vegetation coverage scenario, and integrated scenario) with different albedo and vegetation coverage ratios. In this study, outdoor air temperature, sky view factor, net radiation, mean radiant temperature and thermal radiative power are considered as five criteria for evaluating the efficiency of UHI mitigation strategies. The simulation results of the base model (scenario A) with Osaka's current condition are considered the reference value. The relative percentage differences between each scenario with a base model are determined. The increased albedo of urban fabric material (scenario B Cool pavement model) showed the most efficient to mitigate UHI. The relative percentage differences of the five criteria in the Cool pavement model are more significant than other models. Therefore, the results of this study can provide valuable guidance, both for keeping subtropical residents cooler and informing subtropical climate cities that would be sustainable in the future. • Three main urban heat island (UHI) mitigation strategies in subtropical city centres were reviewed and proposed. • Five scenarios with different albedo and vegetation coverage ratios have been simulated in ENVI-met. • Five criteria are considered as standards to evaluate the efficiency of each UHI mitigation strategy. • The increased albedo of urban pavement fabric material is the most effective way to mitigate UHI in the research city centre. [ABSTRACT FROM AUTHOR]

Skygardens or skycourts are a unique architectural intervention in the built environment, enhancing the social, economic, and environmental values of the building. It allows occupants to connect and experience outdoor freshness within a semi-enclosed environment. However, skygardens located on a highrise building may generate intense wind gusts, endangering the safety of occupants. Using a validated computational fluid dynamics model, this study investigates the potential of various vegetative barriers or shelterbelts in attenuating the high wind speeds encountered in such spaces and the impact on wind and thermal comfort. Three skygarden configurations were investigated with and without vegetative barriers, simplified and modelled as porous zones, and their effect was studied on the velocity and temperature profile at the occupants' level. The results indicate that while hedges and trees can offer resistance to airflow, trees provide higher temperature reduction. However, a combination of vegetative and geometrical barriers provides the most optimal condition in the skygarden. The study has identified the importance of assessing wind attenuation characteristics of tree plantations on highrise skygarden, and the results can be used in designing intervention strategies. Moreover, vegetation can attenuate pollutants and mitigate poor air quality by surface deposition, and future studies should investigate in that direction., Electronic Supplementary Material Esm: The Appendix is available in the online version of this article at 10.1007/s12273-022-0943-7., (© The Author(s) 2022.)

The data presented in this article were the basis for the study reported in the research articles entitled "Evaluation of a two-sided windcatcher integrated with wing wall (as a new design) and comparison with a conventional windcatcher" (P. Nejat, J.K. Calautit, M.Z.A. Majid, B.R. Hughes, I. Zeynali, F. Jomehzadeh, 2016) [1] which presents the effect of wing wall on the air flow distribution under using the windcatchers as a natural ventilation equipment. Here, we detail the wind tunnel testing and numerical set-up used for obtaining the data on ventilation rates and indoor airflow distribution inside a test room with a two-sided windcatcher and wing wall. Three models were integrated with wing wall angled at 30°, 45° and 60° and another windcatcher was a conventional two-sided device. The computer-aided design (CAD) three-dimensional geometries which were produced using Solid Edge modeler are also included in the data article.

This article presents the datasets which were the results of the study explained in the research paper 'Anti-short-circuit device: a new solution for short-circuiting in windcatcher and improvement of natural ventilation performance' (P. Nejat, J.K. Calautit, M.Z. Abd. Majid, B.R. Hughes, F. Jomehzadeh, 2016) [1] which introduces a new technique to reduce or prevent short-circuiting in a two-sided windcatcher and also lowers the indoor CO2 concentration and improve the ventilation distribution. Here, we provide details of the numerical modeling set-up and data collection method to facilitate reproducibility. The datasets includes indoor airflow, ventilation rates and CO2 concentration data at several points in the flow field. The CAD geometry of the windcatcher models are also included.

The data presented in this article were the basis for the study reported in the research articles entitled 'A validated design methodology for a closed loop subsonic wind tunnel' (Calautit et al., 2014) [1], which presented a systematic investigation into the design, simulation and analysis of flow parameters in a wind tunnel using Computational Fluid Dynamics (CFD). The authors evaluated the accuracy of replicating the flow characteristics for which the wind tunnel was designed using numerical simulation. Here, we detail the numerical and experimental set-up for the analysis of the closed-loop subsonic wind tunnel with an empty test section.

The data presented in this article were the basis for the study reported in the research articles entitled 'Climate responsive behaviour heat pipe technology for enhanced passive airside cooling' by Chaudhry and Hughes [10] which presents the passive airside cooling capability of heat pipes in response to gradually varying external temperatures and related to the research article "CFD and wind tunnel study of the performance of a uni-directional wind catcher with heat transfer devices" by Calautit and Hughes [1] which compares the ventilation performance of a standard roof mounted wind catcher and wind catcher incorporating the heat pipe technology. Here, we detail the wind tunnel test set-up and inflow conditions and the methodologies for the transient heat pipe experiment and analysis of the integration of heat pipes within the control domain of a wind catcher design.