Study on the Influence and Optimization of the Venturi Effect on the Natural Ventilation of Buildings in the Xichang Area

Natural ventilation is a way to reduce the energy consumption of building operations and improve the indoor living environment comfort. The venturi cap is designed with a roof, grille and wind deflector to intensify the natural ventilation of buildings. The structural parameters of the venturi cap were designed using an orthogonal design. Fluid analysis software was used for numerical simulation, and variance analysis was used to study the importance of seven influence factors: the width of the roof opening, the roof slope, the height of the wind deflector, the horizontal width of the wind deflector, the angle of the wind deflector, the angle of the grille, and the spacing of the grille slices. The results show that the most significant influencing factor is the width of the roof opening, while significant influence factors include the angle of the grille and the horizontal width of the wind deflector. Additionally, the optimum parameter combination for ventilation performance at the research level was put forward, with the proposed combination achieving a volume flow rate of 5.507 m3/s. The average temperature of the horizontal plane at a height of 1.2 m above the ground was 3.002 K lower than that without a venturi cap, which provides a reference for the optimization of indoor ventilation design in buildings in the Xichang area.

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Comparison of volume flow rate and volume-averaged local mean age of air for evaluating ventilation performance in natural ventilation

Journal of Mechanical Science and Technology ◽

10.1007/s12206-017-1122-0 ◽

2017 ◽

Vol 31 (12) ◽

pp. 5801-5812 ◽

Cited By ~ 2

Author(s):

Jinsoo Park ◽

Gwang Hoon Rhee

Keyword(s):

Flow Rate ◽

Natural Ventilation ◽

Volume Flow Rate ◽

Volume Flow ◽

Local Mean ◽

Ventilation Performance

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The Structure and Fluid Analysis for the New Type of Rotary Tubular Liquid Mixer

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.588-589.1773 ◽

2012 ◽

Vol 588-589 ◽

pp. 1773-1776

Author(s):

Qing Wu ◽

Quan Lai Li ◽

Bao An Han

Keyword(s):

Turbulent Flow ◽

Centrifugal Force ◽

Structural Parameters ◽

Influencing Factor ◽

Mixing Process ◽

Structural Improvement ◽

Fluid Analysis ◽

New Type ◽

Spiral Blade ◽

Rotary Drum

A new type of rotary tubular liquid mixer is proposed in this paper. The tubular rotary drum is rotated with stationary spiral blade fixed inside. The wings are fixed on the blades. The fluid is expelled into the rotary drum and is impinged, separated, flowed around and merged under the effect of centrifugal force and blade hindrance. Then the mixing process is finished. The dimension of mixture structure is reduced, meanwhile the mixture efficiency is enhanced and the mixture effect is strengthened. The practicable turbulent flow in the new rotary tubular liquid mixer is analyzed and the influencing factor is discussed, which provides some proofs for the structural improvement, as well as the selection and optimization of structural parameters.

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Comparison of Downdraught and Up Draft Passive Air Conduction Systems (PACS) in a Winery Building

Buildings ◽

10.3390/buildings11060259 ◽

2021 ◽

Vol 11 (6) ◽

pp. 259

Author(s):

Ádám László Katona ◽

István Ervin Háber ◽

István Kistelegdi

Keyword(s):

Air Conditioning ◽

Natural Ventilation ◽

Dynamics Simulation ◽

Computational Fluid Dynamics Simulation ◽

General Applicability ◽

Change Rate ◽

Air Change Rate ◽

Simulation Based ◽

Ventilation Performance ◽

Air Conduction

A huge portion of energy consumption in buildings comes from heating, ventilation, and air conditioning. Numerous previous works assessed the potential of natural ventilation compared to mechanical ventilation and proved their justification on the field. Nevertheless, it is a major difficulty to collect enough information from the literature to make decisions between different natural ventilation solutions with a given situation and boundary conditions. The current study tests the passive air conduction system (PACS) variations in the design phase of a medium-sized new winery’s cellar and production hall in Villány, Hungary. A computational fluid dynamics simulation based comparative analysis enabled to determine the differences in updraft (UD) and downdraught (DD) PACS, whereby the latter was found to be more efficient. While the DD PACS performed an air change range of 1.02 h−1 to 5.98 h−1, the UD PACS delivered −0.25 h−1 to 12.82 h−1 air change rate. The ventilation performance of the DD version possessed lower amplitudes, but the distribution was more balanced under different wind incident angles, thus this version was chosen for construction. It could be concluded that the DD PACS provides a more general applicability for natural ventilation in moderate climates and in small to medium scale industry hall domains with one in- and one outlet.

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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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05/02299 Natural ventilation performance of a double-skin façade with a solar chimney

Fuel and Energy Abstracts ◽

10.1016/s0140-6701(05)82308-2 ◽

2005 ◽

Vol 46 (5) ◽

pp. 335

Keyword(s):

Natural Ventilation ◽

Solar Chimney ◽

Double Skin ◽

Ventilation Performance

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Microwave-Assisted Leaching Vanadium from Stone Coal

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.189-193.3916 ◽

2011 ◽

Vol 189-193 ◽

pp. 3916-3919 ◽

Cited By ~ 1

Author(s):

Hong Zhou Ma ◽

Xin Zhe Lan ◽

Yao Ning Wang ◽

Yu Hong Tian

Keyword(s):

Sulfuric Acid ◽

Microwave Power ◽

Orthogonal Design ◽

Chemical Constituents ◽

Influence Factors ◽

Sulfate Solution ◽

Leaching Rate ◽

Stone Coal ◽

Microwave Assisted ◽

Design Experiments

Technological process of microwave-assisted leaching of vanadium with sulfate solution has been defined on the base of phase and chemical constituents of stone coal. The influence factors such as content of sulfuric acid, microwave power, and leaching time were studied on leaching rate of vanadium from the stone coal. One element experiments and orthogonal design experiments are carried out to achieve optimized parameters. The experimental results showed that the leaching rate of vanadium was improved by the change of influence factors at some range. The single leaching rate of vanadium reached 80.9% under the optimal conditions of sulfuric acid content of 12%, microwave power 539w,leaching time of 2h.

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A Metawindow with Optimised Acoustic and Ventilation Performance

Applied Sciences ◽

10.3390/app11073168 ◽

2021 ◽

Vol 11 (7) ◽

pp. 3168

Author(s):

Gioia Fusaro ◽

Xiang Yu ◽

Zhenbo Lu ◽

Fangsen Cui ◽

Jian Kang

Keyword(s):

Natural Ventilation ◽

Noise Control ◽

Fem Analysis ◽

The Finite Element Method ◽

Noise Mitigation ◽

Acoustic Performance ◽

Potential Applications ◽

Ventilation Performance ◽

Sound Reduction ◽

Window Design

Crucial factors in window performance, such as natural ventilation and noise control, are generally conceived separately, forcing users to choose one over the other. To solve this dualism, this study aimed to develop an acoustic metamaterial (AMM) ergonomic window design to allow noise control without dependence on the natural ventilation duration and vice versa. First, the finite element method (FEM) was used to investigate the noise control performance of the acoustic metawindow (AMW) unit, followed by anechoic chamber testing, which also served as the validation of the FEM models. Furthermore, FEM analysis was used to optimise the acoustic performance and assess the ventilation potential. The numerical and experimental results exhibited an overall mean sound reduction of 15 dB within a bandwidth of 380 to 5000 Hz. A good agreement between the measured and numerical results was obtained, with a mean variation of 30%. Therefore, the AMW unit optimised acoustic performance, resulting in a higher noise reduction, especially from 50 to 500 Hz. Finally, most of the AMW unit configurations are suitable for natural ventilation, and a dynamic tuned ventilation capacity can be achieved for particular ranges by adjusting the window’s ventilation opening. The proposed designs have potential applications in building acoustics and engineering where natural ventilation and noise mitigation are required to meet regulations simultaneously.

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Optimisation of air-distributor channel structural parameters based on Taguchi orthogonal design

Case Studies in Thermal Engineering ◽

10.1016/j.csite.2020.100685 ◽

2020 ◽

Vol 21 ◽

pp. 100685 ◽

Cited By ~ 1

Author(s):

Guozeng Feng ◽

Shuya Lei ◽

Yuejiao Guo ◽

Dachuan Shi ◽

Jiu Bing Shen

Keyword(s):

Orthogonal Design ◽

Structural Parameters ◽

Taguchi Orthogonal Design

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The Potential of Natural Ventilation in Single-Sided Ventilated Apartment to Improve Indoor Thermal Comfort and Air Quality

ASME 2011 5th International Conference on Energy Sustainability, Parts A, B, and C ◽

10.1115/es2011-54129 ◽

2011 ◽

Cited By ~ 1

Author(s):

M. F. Mohamed ◽

M. Behnia ◽

S. King ◽

D. Prasad

Keyword(s):

Air Quality ◽

Thermal Comfort ◽

Indoor Air Quality ◽

Indoor Air ◽

Natural Ventilation ◽

Architectural Element ◽

Flat Design ◽

Effective Ventilation ◽

Computational Fluid Dynamics Cfd ◽

Ventilation Performance

Cross ventilation is a more effective ventilation strategy in comparison to single-sided ventilation. In the NSW Residential Flat Design Code1 (RFDC) the majority of apartments are required to adopt cross ventilation. However, in the case of studio and one-bedroom apartments, it is acknowledged that single-sided ventilation may prevail. Deep plan studio and one-bedroom apartments may achieve lower amenity of summer thermal comfort and indoor air quality where mechanical ventilation is not provided by air conditioning. Since compliance with the code may allow up to 40% of apartments in a development in Sydney to be single sided, it is important to understand the natural ventilation performance of such apartments. The objective of this paper is to investigate the natural ventilation potential in single-sided ventilated apartments to improve indoor air quality and thermal comfort. This investigation includes simulating various facade treatments involving multiple opening and balcony configurations. Balcony configurations are included in this study because, in Sydney, a balcony is a compulsory architectural element in any apartment building. The study uses computational fluid dynamics (CFD) software to simulate and predict the ventilation performance of each apartment configuration. This study suggests that properly configured balconies and openings can significantly improve indoor ventilation performance for enhanced indoor air quality and thermal comfort, by optimizing the available prevailing wind. However, it is important to note that inappropriately designed fac¸ade treatments also could diminish natural ventilation performance.

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