Field Monitoring of the Natural Ventilation Rate of Residential Buildings in Beijing

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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The impacts of introducing voids combinations on indoor ventilation performance in high-rise residential buildings

Engineering Construction & Architectural Management ◽

10.1108/ecam-09-2020-0752 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Hamza Laloui ◽

Noor Hanita Abdul Majid ◽

Aliyah Nur Zafirah Sanusi

Keyword(s):

Architectural Design ◽

Natural Ventilation ◽

Residential Buildings ◽

Design Feature ◽

Field Measurements ◽

Ventilation Rate ◽

Content Type ◽

High Rise ◽

Building Models ◽

Ventilation Performance

PurposeThe paper aims to investigate and evaluate the impacts of the voids combination as a passive design feature on wind-driven ventilation performance in high-rise residential building units. It proposes a series of building models and thereon indoor ventilation performance and outlining why and how these building models designed with architectural design features are important. This study aims to provide a comprehensive understanding of how natural ventilation as a passive cooling strategy in living units of high-rise residential buildings can be applied through improving the provision of the architectural design feature of voids configurations.Design/methodology/approachThe study was carried out through field measurements experiment and the computational fluid dynamics methods. A series of numerical simulations were carried out to calculate the indoor ventilation rate inside the case studies of the generated building models based on various variables such as horizontal voids type, size and wind directions.FindingsThe results indicate that the provision of a single-sided horizontal voids in building models can improve the indoor ventilation rate in units with cross ventilation mode up to 4 times, depending on wind direction and living unit location. The indoor ventilation performance in units located in models with single-sided horizontal voids is 17.54% higher than the units located in models without voids configuration. Furthermore, higher indoor ventilation performance was achieved in the case scenarios located at higher levels compared to the middle and lower levels in both horizontal voids types.Originality/valueThis study explores the application of voids combinations for natural ventilation performance, investigates the numerical simulation results and validates field measurements experiment data using CFD simulation.

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Climatic Envelope as an Urban Planning Tool to Configure Urban Fabric of Guwahati City to Support Daylight and Natural Ventilation

International Journal of Engineering and Advanced Technology - Regular Issue ◽

10.35940/ijeat.c2208.0210321 ◽

2021 ◽

Vol 10 (3) ◽

pp. 239-248

Author(s):

Amal Barman ◽

Madhumita Roy ◽

Arpan Dasgupta

Keyword(s):

Urban Growth ◽

Natural Ventilation ◽

Residential Buildings ◽

Spatial Arrangement ◽

Ventilation Rate ◽

Building Envelope ◽

Urban Fabric ◽

Guwahati City ◽

Climatic Envelope ◽

Residential Neighbourhood

Over the last decade, as a result of rapid urban growth and increasing human population, Guwahati city is witnessing multilayered transformation owing to socio-economic, geo-political and technological issues. This constant increase of built form is resulting haphazard urban growth pattern in down town city areas sacrificing the access to daylight and solar radiation inside residential buildings. Even though the development pattern of Guwahati is controlled by established GMDA building bye-laws; these building regulations and guidelines are unable to control the organic growth of the city since there is no climate-sensitive approach available in the existing GMDA bye-laws. This paper aims to discuss the likelihood of constructing a composite climatic envelope by using daylight spacing angle and solar elevation angle techniques within the residential zone of Guwahati city. This paper also analyses how climatic envelope technique helps to establish an efficient height-to-width (H/W) ratio in spatial arrangement of residential neighbourhood and ensures a higher levels of daylight factor (DF), permits solar access to the neighboring buildings and also enables better ventilation rate inside every rooms of residential buildings. This paper analyses further to discuss about the performance of natural ventilation inside building envelope and reviews the common energy code of openable window to floor area (WFRop) ratio in urban residential buildings. During this study, an existing urban spatial arrangement of residential neighbourhood under GMDA jurisdiction is studied, discussed and analysed. Results of this study, plotting H/W ratio against average daylight factor and ventilation rate can be used as a preliminary urban design tool to configure the urban fabric especially within the residential zone of GMDA area.

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Thermal Performance of Single-Story Air-Welled Terraced House in Malaysia: A Field Measurement Approach

Sustainability ◽

10.3390/su13010201 ◽

2020 ◽

Vol 13 (1) ◽

pp. 201

Author(s):

Pau Chung Leng ◽

Gabriel Hoh Teck Ling ◽

Mohd Hamdan Ahmad ◽

Dilshan Remaz Ossen ◽

Eeydzah Aminudin ◽

...

Keyword(s):

Relative Humidity ◽

Air Temperature ◽

Thermal Performance ◽

Field Measurement ◽

Natural Ventilation ◽

Residential Buildings ◽

Wet Bulb Globe Temperature ◽

Natural Lighting ◽

Ventilation Performance ◽

Globe Temperature

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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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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The Green Building Environment of the Gymnasium

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.878.202 ◽

2018 ◽

Vol 878 ◽

pp. 202-209 ◽

Cited By ~ 1

Author(s):

Feng Qian ◽

Li Yang

Keyword(s):

Natural Ventilation ◽

Residential Buildings ◽

Green Building ◽

Residential Area ◽

Simulation Software ◽

Living Environment ◽

Outdoor Environment ◽

Residential Areas ◽

Outdoor Environments ◽

Area Planning

The natural ventilation of residential areas has placed more and more emphasis on residential area planning, according to the relationship between natural ventilation environments and the layout of architecture, we can reduce the energy consumption and the adverse effect of wind outdoors, improve the living environment and quality of life, making harmony between human and the nature. In this paper, we use Air-Pak to simulate the wind environment of residential areas. Through analyzing and simulating the air field which forms when the wind blows around the residential buildings by Air-Pak, we explain the advantage of the combination of computer simulation software and residential area planning. And we give some advice to the layout of the outdoor environment early in the residential planning area by the simulation of outdoor environments of buildings.

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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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On the thermal buffering of naturally ventilated buildings through internal thermal mass

Journal of Fluid Mechanics ◽

10.1017/s0022112007005320 ◽

2007 ◽

Vol 580 ◽

pp. 3-29 ◽

Cited By ~ 24

Author(s):

J. M. HOLFORD ◽

A. W. WOODS

Keyword(s):

Heat Exchange ◽

Air Temperature ◽

Natural Ventilation ◽

Ventilation Rate ◽

Temperature Cycle ◽

Thermal Mass ◽

Thermal Equilibration ◽

Environment Temperature ◽

Naturally Ventilated Buildings ◽

Diurnal Fluctuations

In this paper we examine the role of thermal mass in buffering the interior temperature of a naturally ventilated building from the diurnal fluctuations in the environment. First, we show that the effective thermal mass which is in good thermal contact with the air is limited by the diffusion distance into the thermal mass over one diurnal temperature cycle. We also show that this effective thermal mass may be modelled as an isothermal mass. Temperature fluctuations in the effective thermal mass are attenuated and phase-shifted from those of the interior air, and therefore heat is exchanged with the interior air. The evolution of the interior air temperature is then controlled by the relative magnitudes of (i) the time for the heat exchange between the effective thermal mass and the air; (ii) the time for the natural ventilation to replace the air in the space with air from the environment; and (iii) the period of the diurnal oscillations of the environment. Through analysis and numerical solution of the governing equations, we characterize a number of different limiting cases. If the ventilation rate is very small, then the thermal mass buffers the interior air temperature from fluctuations in the environment, creating a near-isothermal interior. If the ventilation rate increases, so that there are many air changes over the course of a day, but if there is little heat exchange between the thermal mass and interior air, then the interior air temperature locks on to the environment temperature. If there is rapid thermal equilibration of the thermal mass and interior air, and a high ventilation rate, then both the thermal mass and the interior air temperatures lock on to the environment temperature. However, in many buildings, the more usual case is that in which the time for thermal equilibration is comparable to the period of diurnal fluctuations, and in which ventilation rates are moderate. In this case, the fluctuations of the temperature of the thermal mass lag those of the interior air, which in turn lag those of the environment. We consider the implications of these results for the use of thermal mass in naturally ventilated buildings.

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