Wind pressure distribution influence on natural ventilation for different incidences and environment densities

This paper aims to study the wind flow characteristics and to analyze the wind pressure distribution on the surfaces around an irregular octagonal plan shape building model. There is a central open space in plan to provide more surface area around the building for natural ventilation. Plan area of the building is 300 m2(excluding the open space) and height is 50 m. Steady state flow of wind with 5% turbulence (moderate turbulence) under atmospheric boundary layer has been taken in the study. Numerical simulation with standard k-e model using ANSYS (CFX) software has been used for the purpose. Flow characteristics has been studied in terms of flow separation, reattachment of flow, creation of wakes and vortices. The surface pressure generated around the model has been studied in terms of coefficient of pressure. The model is symmetrical about both the axes in plan. Hence, study for different wind angle of attacks from 0° to 90° @ 30° interval has been conducted. The flow characteristics and unusual or critical coefficient of pressure on surfaces of the model observed have been discussed. Doi: 10.28991/cej-2021-03091760 Full Text: PDF

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Investigating the Effect of Balcony Types on the Naturally-Ventilated Buildings

Journal of Sustainable Architecture and Civil Engineering ◽

10.5755/j01.sace.26.1.24318 ◽

2020 ◽

Vol 26 (1) ◽

pp. 74-86

Author(s):

Elahe Mirabi ◽

Nazanin Nasrollahi ◽

Mehdi Dadkhah

Keyword(s):

Pressure Distribution ◽

Pressure Difference ◽

Natural Ventilation ◽

Air Flow ◽

Wind Pressure ◽

Basic Rule ◽

Ansys Fluent ◽

Interior Spaces ◽

Complicated Pattern ◽

Naturally Ventilated Buildings

Natural ventilation is application of natural drift power of wind. Wind can enter and exit buildings through the openings on facades. Hence, Form of facades can impact the air flow behaviour and consequently natural ventilation because they can change the pressure distribution on facades. Moreover, wind pressure difference between windward and leeward facades of buildings is the most important factor affecting natural ventilation. So, it is worthy to focus on facade details in order to enhance natural ventilation. Particularly, geometrical details of facades such as protrusions and indentations e.g. balconies can be considered effective elements on average pressure distribution on both windward and leeward facades, changing pressure difference between these facades. This difference can drive the air flow towards interior spaces significantly. Although this basic rule has been used by different researchers in order to increase natural ventilation buildings, the most research has been studied buildings with flat facades. Therefore, this study aims to investigate effects of balcony types on the natural ventilation. Three types of balcony are simulated and the wind pressure distribution on the windward and leeward facades are analysed. All these simulations are carried out for normally (perpendicular) and obliquely incident wind. This study is performed with Ansys Fluent 18 for all simulations. The results showed that balcony types can affect the pressure distribution on the windward and leeward facades of buildings, leading to the more or less pressure difference between these two facades. These results show that protrusion (protrusive balcony) can cause more complicated pattern of the wind pressure on facades than the others. Also, Re-entrant balcony causes the more pressure differences between the windward and leeward facades and enhances natural ventilation of buildings more considerably than the protrusive one.

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06/00258 Wind pressure distribution influence on natural ventilation for different incidences and environment densities

Fuel and Energy Abstracts ◽

10.1016/s0140-6701(06)80258-4 ◽

2006 ◽

Vol 47 (1) ◽

pp. 36

Keyword(s):

Pressure Distribution ◽

Natural Ventilation ◽

Wind Pressure

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Effect of Corner Configuration on Wind Pressure Distribution on Tall Buildings

International Journal of Earth Sciences and Engineering ◽

10.21276/ijee.2017.10.0243 ◽

2017 ◽

Vol 10 (02) ◽

pp. 418-426

Author(s):

ADAL MENGESHA YIMER ◽

ASHOK KUMAR AHUJA

Keyword(s):

Pressure Distribution ◽

Tall Buildings ◽

Wind Pressure

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CFD Modeling of Pressure Coefficients for a Natural Ventilation Study in an Experimental Low Rise Building

Volume 6B: Energy ◽

10.1115/imece2013-66789 ◽

2013 ◽

Author(s):

Robel Kiflemariam ◽

Cheng-Xian Lin

Keyword(s):

Natural Ventilation ◽

Pressure Coefficient ◽

Wind Pressure ◽

Analytical Models ◽

Cfd Modeling ◽

Engineering Practice ◽

Pressure Coefficients ◽

Wind Pressure Coefficient ◽

Detailed Assessment ◽

Ventilation Rates

Mean wind pressure coefficient (Cp) is one of the major input data for natural ventilation study using building energy simulation approach. Due to their importance, they need to be accurately determined. In current engineering practice, tables and analytical Cp models only give mostly averaged results for simpler models and configurations. Considering the limitation of tables and analytical models, Computational Fluid Dynamics (CFD) could provide a means for an accurate and detailed assessment of Cp. In this paper, we make use of a relatively high resolution, detailed experiments done at Florida Intentional University to validate a CFD modeling of the pressure coefficients Cp. The results show that existing CFD model has a good agreement with experimental results and gives important information of distribution of Cp values over the surface. The local values of the Cp are investigated. In addition, the CFD derived Cp and discharge coefficient (Cd) values are utilized in semi-analytical ventilation models in order to get a more accurate value of ventilation rates.

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