View in EDS

Effect of outdoor wind on the hybrid natural ventilation performance of monitor roofs.

Saved in:
Bibliographic Details
Title: Effect of outdoor wind on the hybrid natural ventilation performance of monitor roofs.
Authors: Lin, Yi-Pin1 (AUTHOR), Huang, Tzu-Ling2 (AUTHOR), Chung, Sung-Chin1 (AUTHOR), Lai, Chi-Ming1,3 (AUTHOR) cmlai@mail.ncku.edu.tw
Source: Alexandria Engineering Journal. Oct2023, Vol. 80, p584-593. 10p.
Subjects: Natural ventilation, Computational fluid dynamics, Ventilation monitoring, Reynolds number, Ventilation
Abstract: The monitor roof of a building has a raised structure running along the gable ridge, with its smaller roof parallel to the lower main roof. As a common building ventilation design, monitor roofs are expected to induce indoor airflow through thermal buoyancy and/or wind; however, studies on the design details and the induced natural ventilation performance are limited. In this study, how outdoor wind affects the efficiency of induced hybrid natural ventilation of monitor roofs was analyzed through computational fluid dynamics (CFD). Based on engineering practice and weather conditions, the Grashof number (Gr) was 2.11 x 10 11 - 5.67 x 10 11 , and the Reynolds number (Re) was 2. 5 x 10 5 - 1. 7 x 10 6. The results indicated that for a larger monitor roof (width = 3 m, height = 1.2 m), the presence of outdoor wind combined with thermal buoyancy increased the ventilation rate to 1.5–3.5 times that found when only buoyancy was present. For a smaller monitor roof (width = 1.2 m, height = 0.3 m), Gr/Re2 = 0.45–3.2 was the transition range over which the presence of outdoor wind decreased the ventilation rate below that found when only buoyancy was present. Therefore, attention should be given to this disadvantage in ventilation design. [ABSTRACT FROM AUTHOR]
Copyright of Alexandria Engineering Journal is the property of Elsevier B.V. and its content may not be copied or emailed to multiple sites without the copyright holder's express written permission. Additionally, content may not be used with any artificial intelligence tools or machine learning technologies. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)
Database: Engineering Source
Description
Abstract:The monitor roof of a building has a raised structure running along the gable ridge, with its smaller roof parallel to the lower main roof. As a common building ventilation design, monitor roofs are expected to induce indoor airflow through thermal buoyancy and/or wind; however, studies on the design details and the induced natural ventilation performance are limited. In this study, how outdoor wind affects the efficiency of induced hybrid natural ventilation of monitor roofs was analyzed through computational fluid dynamics (CFD). Based on engineering practice and weather conditions, the Grashof number (Gr) was 2.11 x 10 11 - 5.67 x 10 11 , and the Reynolds number (Re) was 2. 5 x 10 5 - 1. 7 x 10 6. The results indicated that for a larger monitor roof (width = 3 m, height = 1.2 m), the presence of outdoor wind combined with thermal buoyancy increased the ventilation rate to 1.5–3.5 times that found when only buoyancy was present. For a smaller monitor roof (width = 1.2 m, height = 0.3 m), Gr/Re2 = 0.45–3.2 was the transition range over which the presence of outdoor wind decreased the ventilation rate below that found when only buoyancy was present. Therefore, attention should be given to this disadvantage in ventilation design. [ABSTRACT FROM AUTHOR]
ISSN:11100168
DOI:10.1016/j.aej.2023.09.014