Field measurement of natural ventilation rate in an idealised full-scale building located in a staggered urban array: Comparison between tracer gas and pressure-based methods

The provision requirement of 10% openings of the total floor area stated in the Uniform Building By-Law 1984 Malaysia is essential for natural lighting and ventilation purposes. However, focusing on natural ventilation, the effectiveness of thermal performance in landed residential buildings has never been empirically measured and proven, as most of the research emphasized simulation modeling lacking sufficient empirical validation. Therefore, this paper drawing on field measurement investigates natural ventilation performance in terraced housing with an air-well system. The key concern as to what extent the current air-well system serving as a ventilator is effective to provide better thermal performance is to be addressed. By adopting an existing single-story air-welled terrace house, indoor environmental conditions and thermal performance were monitored and measured using HOBO U12 air temperature and humidity, the HOBO U12 anemometer, and the Delta Ohm HD32.3 Wet Bulb Globe Temperature meter for a six-month duration. The results show that the air temperature of the air well ranged from 27.48 °C to 30.92 °C, with a mean relative humidity of 72.67% to 79.25%. The mean air temperature for a test room (single-sided ventilation room) ranged from 28.04 °C to 30.92 °C, with a relative humidity of 70.16% to 76.00%. These empirical findings are of importance, offering novel policy insights and suggestions. Since the minimum provision of 10% openings has been revealed to be less effective to provide desirable thermal performance and comfort, mandatory compliance with and the necessity of the bylaw requirement should be revisited.

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Proposing Alternative Solutions to Enhance Natural Ventilation Rates in Residential Buildings in the Cfa Climate Zone of Rasht

Sustainability ◽

10.3390/su13020679 ◽

2021 ◽

Vol 13 (2) ◽

pp. 679

Author(s):

Roya Aeinehvand ◽

Amiraslan Darvish ◽

Abdollah Baghaei Daemei ◽

Shima Barati ◽

Asma Jamali ◽

...

Keyword(s):

Natural Ventilation ◽

Residential Buildings ◽

Residential Building ◽

Ventilation Rate ◽

Humid Climate ◽

The Sustainable Development ◽

Passive Strategies ◽

Development Goals ◽

Ventilation Rates ◽

Ventilation Systems

Today, renewable resources and the crucial role of passive strategies in energy efficiency in the building sector toward the sustainable development goals are more indispensable than ever. Natural ventilation has traditionally been considered as one of the most fundamental techniques to decrease energy usage by building dwellers and designers. The main purpose of the present study is to enhance the natural ventilation rates in an existing six-story residential building situated in the humid climate of Rasht during the summertime. On this basis, two types of ventilation systems, the Double-Skin Facade Twin Face System (DSF-TFS) and Single-Sided Wind Tower (SSWT), were simulated through DesignBuilder version 4.5. Then, two types of additional ventilation systems were proposed in order to accelerate the airflow, including four-sided as well as multi-opening wind towers. The wind foldable directions were at about 45 degrees (northwest to southeast). The simulation results show that SSWT could have a better performance than the aforementioned systems by about 38%. Therefore, the multi-opening system was able to enhance the ventilation rate by approximately 10% during the summertime.

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Natural-Ventilation Flow in a 3-D Room Fitted With Solar Chimney

Volume 7: Fluids and Heat Transfer, Parts A, B, C, and D ◽

10.1115/imece2012-87455 ◽

2012 ◽

Author(s):

B. P. Huynh

Keyword(s):

Heat Flux ◽

Flow Pattern ◽

Natural Ventilation ◽

Air Flow ◽

Ventilation Rate ◽

High Heat Flux ◽

Solar Chimney ◽

Solar Heat ◽

Solar Heat Flux ◽

Inlet Opening

Natural-ventilation flow induced in a real-sized rectangular-box room fitted with a solar chimney on its roof is investigated numerically, using a commercial CFD (Computational Fluid Dynamics) software package. The chimney in turn is in the form of a parallel channel with one plate being subjected to uniform solar heat flux. Ventilation rate and air-flow pattern through the room are considered in terms of the heat flux for two different locations of the room’s inlet opening. Chien’s turbulence model of low-Reynolds-number K-ε is used in a Reynolds-Averaged Navier-Stokes (RANS) formulation. It is found that ventilation flow rate increases quickly with solar heat flux when this flux is low, but more gradually at higher flux. At low heat flux, ventilation rate is not significantly affected by location of the inlet opening to the room. On the other hand, at high heat flux, ventilation rate varies substantially with the opening’s location. Location of the inlet opening to the room also affects strongly the air-flow pattern. In any case, ample ventilation rate is readily induced by the chimney.

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Comprehensive validation of experimental and numerical natural ventilation predictions based on field measurement with experimental house

Building and Environment ◽

10.1016/j.buildenv.2021.108433 ◽

2022 ◽

Vol 207 ◽

pp. 108433

Author(s):

Hong Hu ◽

Hideki Kikumoto ◽

Ryozo Ooka ◽

Chao Lin ◽

Bingchao Zhang

Keyword(s):

Field Measurement ◽

Natural Ventilation

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Effect of natural ventilation mode on thermal comfort and ventilation performance: Full-scale measurement

Energy and Buildings ◽

10.1016/j.enbuild.2017.09.061 ◽

2017 ◽

Vol 156 ◽

pp. 1-16 ◽

Cited By ~ 17

Author(s):

Sara Omrani ◽

Veronica Garcia-Hansen ◽

Bianca R. Capra ◽

Robin Drogemuller

Keyword(s):

Thermal Comfort ◽

Natural Ventilation ◽

Full Scale ◽

Ventilation Mode ◽

Ventilation Performance

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The Role of Ab-Anbars in the Vernacular Architecture of Iran with Emphasis on the Performance of Wind-Catchers in Hot and Dry Climates

Heritage ◽

10.3390/heritage4040219 ◽

2021 ◽

Vol 4 (4) ◽

pp. 3987-4000

Author(s):

Fazeleh Yousefi ◽

Francesco Nocera

Keyword(s):

Natural Ventilation ◽

Vernacular Architecture ◽

Ventilation Rate ◽

The People ◽

Desert Areas ◽

Dry Climates ◽

Yazd City ◽

Cooling Loads ◽

Contemporary Architecture

Vernacular and traditional Iranian architecture has always acted rationally, harmoniously, and climate-friendly to meet the needs of the people in dealing with the environment. In addition, without harming the environment, they have achieved the best initiatives with the least facilities. For example, we can mention that the Ab-Anbars in arid and desert areas of Iran, which are used to store water in seasons with precipitation for use in the rest of the year, has been an optimal way to use natural resources and provide climate comfort. The Ab-Anbars are realized with ventilated cisterns through openings on their roof or wind-catchers to keep the water cool and provide comfortable conditions for the occupants. In order to study the essential role of natural ventilation and cooling in the Ab-Anbars, thermal analysis with CFD software was carried out to assess the effectiveness of a typical wind-catcher according to different wind directions in Yazd city. The results showed that Ab-Anbars have played an important role in reducing cooling loads and supply the necessary ventilation rate of buildings and can be used in the future for application in contemporary architecture and urban planning.

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Small and Full-Scale Modeling for the Application of Wall Solar Chimneys

Volume 1A, Symposia: Turbomachinery Flow Simulation and Optimization; Applications in CFD; Bio-Inspired and Bio-Medical Fluid Mechanics; CFD Verification and Validation; Development and Applications of Immersed Boundary Methods; DNS, LES and Hybrid RANS/LES Methods; Fluid Machinery; Fluid-Structure Interaction and Flow-Induced Noise in Industrial Applications; Flow Applications in Aerospace; Active Fluid Dynamics and Flow Control — Theory, Experiments and Implementation ◽

10.1115/fedsm2016-7639 ◽

2016 ◽

Author(s):

David Park ◽

Francine Battaglia

Keyword(s):

Natural Ventilation ◽

Velocity Ratio ◽

Thermal Conditions ◽

Ambient Air ◽

Full Scale ◽

Scale Model ◽

Small Scale ◽

Solar Chimney ◽

Window Position ◽

Pi Theorem

A solar chimney is a natural ventilation technique that has a potential to save energy consumption as well as to maintain the air quality in the building. However, studies of buildings are often challenging due to their large sizes. The objective of the current study was to determine relationships between small- and full-scale solar chimney system models. In the current work, computational fluid dynamics (CFD) was utilized to model different building sizes with a solar chimney system, where the computational model was validated with the experimental study of Mathur et al. The window, which controls entrainment of ambient air, was also studied to determine the effects of window position. Correlations for average velocity ratio and non-dimensional temperature were consistent regardless of window position. Buckingham pi theorem was employed to further non-dimensionalize the important variables. Regression analysis was conducted to develop a mathematical model to predict a relationship among all of the variables, where the model agreed well with simulation results with an error of 2.33%. The study demonstrated that the flow and thermal conditions in larger buildings can be predicted from the small-scale model.

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