CFD Analysis of an Innovative Wind Tower Design with Wind-Inducing Natural Ventilation Technique for Arid Climatic Conditions

The wind catcher or wind tower is a natural ventilation technique that has been employed in the Middle East region and still until nowadays. The present paper aims to study the effect of the one-sided position of a wind catcher device against the ventilated space or building geometry and its natural ventilation performance. Four models based on the traditional design of a one-sided wind catcher are studied and compared. The study is achieved under the climatic conditions of the South-west of Algeria (arid region). The obtained results showed that the front and Takhtabush’s models were able to create the maximum pressure difference (ΔP) between the windward and leeward of the tower-house system. Internal airflow velocities increased with the increase of wind speed in all studied models. For example, at Vwind = 2 m/s, the internal flow velocities were 1.7, 1.8, 1.3, and 2.5 m/s for model 1, 2, 3, and 4, respectively. However, at Vwind = 6 m/s, the internal flow velocities were 5.6, 5.5, 2.5, and 7 m/s for model 1, 2, 3, and 4, respectively. The higher internal airflow velocities are given by Takhtabush, traditional, front and middle tower models, respectively, with a reduction rate between the tower outlet and occupied space by 72, 42, 36, and 33% for the middle tower, Takhtabush, traditional tower, and the front model tower, respectively. This reduction is due to the due to internal flow resistance. The third part of the study investigates the effect of window (exist opening) position on the opposite wall. The upper, middle and lower window positions are studied and compared. The air stagnation or recirculation zone inside the ventilated space reduced from 55% with the lower window to 46% for the middle window and reached 35% for the upper window position. The Front and Takhtabush models for the one-sided wind catcher with an upper window position are highly recommended for the wind-driven natural ventilation in residential houses that are located in arid regions.

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Review of Intelligent Control Systems for Natural Ventilation as Passive Cooling Strategy for UK Buildings and Similar Climatic Conditions

Energies ◽

10.3390/en14154388 ◽

2021 ◽

Vol 14 (15) ◽

pp. 4388

Author(s):

Esmail Mahmoudi Saber ◽

Issa Chaer ◽

Aaron Gillich ◽

Bukola Grace Ekpeti

Keyword(s):

Control Systems ◽

Natural Ventilation ◽

Energy Use ◽

Integrated Control ◽

Climatic Conditions ◽

Effective Control ◽

Practical Implementation ◽

Optimal Output ◽

Heating And Cooling ◽

Building Cooling

Natural ventilation is gaining more attention from architects and engineers as an alternative way of cooling and ventilating indoor spaces. Based on building types, it could save between 13 and 40% of the building cooling energy use. However, this needs to be implemented and operated with a well-designed and integrated control system to avoid triggering discomfort for occupants. This paper seeks to review, discuss, and contribute to existing knowledge on the application of control systems and optimisation theories of naturally ventilated buildings to produce the best performance. The study finally presents an outstanding theoretical context and practical implementation for researchers seeking to explore the use of intelligent controls for optimal output in the pursuit to help solve intricate control problems in the building industry and suggests advanced control systems such as fuzzy logic control as an effective control strategy for an integrated control of ventilation, heating and cooling systems.

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Indoor Climate Performance in a Renovated School Building

Energies ◽

10.3390/en14102827 ◽

2021 ◽

Vol 14 (10) ◽

pp. 2827

Author(s):

Pavla Mocová ◽

Jitka Mohelníková

Keyword(s):

Indoor Environment ◽

Natural Ventilation ◽

Carbon Dioxide Concentration ◽

Heating System ◽

Climatic Conditions ◽

School Building ◽

Ventilation Strategy ◽

Indoor Climate ◽

Microbiological Testing ◽

Indoor Comfort

Indoor climate comfort is important for school buildings. Nowadays, this is a topical problem, especially in renovated buildings. Poorly ventilated school classrooms create improper conditions for classrooms. A post-occupancy study was performed in a school building in temperate climatic conditions. The evaluation was based on the results of long-term monitoring of the natural ventilation strategy and measurements of the carbon dioxide concentration in the school classroom’s indoor environment. The monitoring was carried out in an old school building that was constructed in the 1970s and compared to testing carried out in the same school classroom after the building was renovated in 2016. Surprisingly, the renovated classroom had a significantly higher concentration of CO2. It was found that this was due to the regulation of the heating system and the new airtight windows. The occupants of the renovated classroom have a maintained thermal comfort, but natural ventilation is rather neglected. A controlled ventilation strategy and installation of heat recovery units are recommended to solve these problems with the classroom’s indoor environment. Microbiological testing of the surfaces in school classrooms also shows the importance of fresh air and solar radiation access for indoor comfort.

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Acoustic Performance of Louvred Facades for Brisbane Domestic Airport: An Integrated Approach

ASME 2012 Noise Control and Acoustics Division Conference ◽

10.1115/ncad2012-1393 ◽

2012 ◽

Author(s):

Frank Butera ◽

Keith Hewett

Keyword(s):

Natural Ventilation ◽

Transmission Loss ◽

Internal Noise ◽

Building Design ◽

Integrated Approach ◽

External Noise ◽

Climatic Conditions ◽

Sustainable Building ◽

Heating And Cooling ◽

Airport Terminals

Maximising cross ventilation is a low energy method of naturally ventilating and providing heating and cooling to deep plan spaces. Significant reduction in the emission of greenhouse gases can be achieved through minimising the use of mechanical systems in regions with climatic conditions that support the use of natural ventilation. Arup has provided input into the design of a louvered facade for the control of external noise for Brisbane Domestic Airport. A full scale prototype facade was constructed and noise transmission loss measurements were undertaken. The results indicate that significant noise reduction can be achieved to enable compliance with the internal noise limits for airport terminals, whilst using natural ventilation. The findings from this research will directly benefit building designers and innovators in the pursuit of achieving sustainable building design.

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Enhancement of Gravity Ventilation in Buildings

Proccedings of 10th International Conference "Environmental Engineering" ◽

10.3846/enviro.2017.269 ◽

2017 ◽

Author(s):

Magdalena Nakielska ◽

Krzysztof Pawłowski

Keyword(s):

Natural Ventilation ◽

Air Flow ◽

Electrical Energy ◽

Climatic Conditions ◽

Demand Systems ◽

Solar Chimney ◽

Correct Operation ◽

Research Results ◽

Heat Demand ◽

Flow Through

Nowadays, people are looking for solutions related to ventilation, cooling or heat demand systems, which would be energy efficient and, at the same time, would not cause the degradation of the surrounding environment. As far as ventilation is concerned, an good solution is a natural ventilation, which improves thermal comfort rooms without increasing the consumption of electrical energy in the building. In order to improve the mode of action of the natural ventilation in the building, one can mount various elements supporting the air flow. One of them is a solar chimney. In order to check the correct operation of a gravity ventilation installation in Poland’s climatic conditions, the measurements was carried out on a test stand on the 3.1 building of UTP University of Science and Technology in Bydgoszcz. The received results show the intensification of the air flow through the room the value between 50% and 150%, depending on a measuring hour (Chen et al. 2003). These research results were compared with the research results received before the installation of the solar chimney on the ducts of the gravity ventilation.

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Numerical simulations for the optimisation of ventilation system designed for wine cellars

Journal of Agricultural Engineering ◽

10.4081/jae.2019.952 ◽

2019 ◽

Vol 50 (4) ◽

pp. 180-190 ◽

Cited By ~ 2

Author(s):

Enrica Santolini ◽

Alberto Barbaresi ◽

Daniele Torreggiani ◽

Patrizia Tassinari

Keyword(s):

Natural Ventilation ◽

Ventilation System ◽

Climatic Conditions ◽

Mold Growth ◽

Critical Factors ◽

Air Velocity ◽

Wine Production ◽

First Case ◽

Dynamics Modelling ◽

Optimal Configurations

The wine-ageing process is one of the most important phases of the wine production and it can be considerably affected by the micro-climatic conditions inside the ageing rooms. Underground wine cellars in small-medium wineries are designed with natural ventilation systems, able to maintain optimal indoor condition. However, critical factors emerge, such as mold growth or wine evapo-transpiration, where ventilation proved to be poorly designed, insufficient in the first case or excessive in the second one. The zones around the wooden barrels proved to be the most sensitive and problematic. These areas are the most investigated in terms of temperature and humidity values but surprisingly not in terms of air velocity. In this paper, a ventilation system has been designed and optimised to support the lack of ventilation, by means of computational fluid dynamics modelling. Eight configurations have been performed and analysed, identifying the best two according to the air velocity range. Specific parameters have been defined to appreciate the application limits of each configuration. These parameters can be used as reference for system design in similar studies and applications and can help scholars and professionals to identify the optimal configurations for the implementation and proper placement of the system inside a cellar.

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Analysis of Heavy Organic Fluids Dispersion Inside Industrial Buildings Hosting Turbomachinery Test Facilities

Volume 1: Advances in Solar Buildings and Conservation; Climate Control and the Environment; Alternate Fuels and Infrastructure; ARPA-E; Combined Energy Cycles, CHP, CCHP, and Smart Grids; Concentrating Solar Power; Economic, Environmental, and Policy Aspects of Alternate Energy; Geothermal Energy, Harvesting, Ocean Energy and Other Emerging Technologies; Hydrogen Energy Technologies; Low/Zero Emission Power Plants and Carbon Sequestration; Micro and Nano Technology Applications and Materials ◽

10.1115/es2015-49364 ◽

2015 ◽

Author(s):

Daniele Fiaschi ◽

Giampaolo Manfrida ◽

Luigi Russo

Keyword(s):

Natural Ventilation ◽

Health And Safety ◽

Climatic Conditions ◽

Building Envelope ◽

Industrial Building ◽

Gas Emissions ◽

Test Gas ◽

Industrial Buildings ◽

Test Circuit ◽

Organic Fluids

The use of heavy fluids (typically refrigerants) for tests on turbomachinery equipment, like centrifugal compressors, under similitude with real working conditions is a common practice in the test facilities of manufacturers. This practice leads to the release of the test gas to the environment, mainly coming from seals, test circuit connections, valve gaskets and from operations of circuit assembling/disassembling necessary to replace or service the machine under test. The spatial distribution and flow of these emissions inside the test building is a complex issue, which depends on the specific circuit features, location of sources, geometry and openings of the building and variable climatic conditions of the location. For a preliminary assessment of the health and safety conditions, a NIST computational package — including a CFD solver — was applied. The aim was to validate the applicability and reliability of this tool, which was developed for other types of buildings; from the industrial side, knowledge of the diffusion scenario is important to define test protocols to guarantee acceptable emissions levels for manpower in working areas. The industrial building is organized in multiple inside workspaces. The concentration of the contaminant in the area of the test benches, determined by the internal fluid dynamics, is calculated with the CFD solver included in the NIST package. In the building, air motion is only affected by natural ventilation. For this reason, the interactions between the outside and the interior climatic and microclimatic parameters must be considered, taking into account also the different possible assumptions about the daily management of the openings of the building envelope. Several cases of release and dispersion of heavy fluid inside the working areas, under different boundary conditions, were considered. The sensitivity of the results to the different seasonal conditions was assessed and discussed. The complex internal geometry of the building was simulated by a combination of single zone models. The results showed an expectable presence of test gas emissions in the neighborhood of the test area and the possibility of buoyancy effects within the large building. A relatively stable concentration of the test gas emissions resulted from the application of the model, which was affected only by substantial variations of the climatic conditions.

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