Analysis of Capture Velocity in the Case of Local Exhaust Ventilation
Publication: Journal of Architectural Engineering
Volume 30, Issue 2
Abstract
This article presents a study on the capture velocity of local exhaust ventilation (LEV) using a specially designed workstation within a laboratory setting. The workstation featured a worktop with dimensions of 90 cm width and 45 cm depth, and the exhaust duct was positioned near the pollutant source, considering the intended operation of the LEV system. The worktop was divided into squares for precise documentation and remeasurement. A supply duct above the worktop provided controlled fresh airflow. Smoke was used to visualize airflow patterns. The measurements focused on air velocity and turbulence intensity, aiming to understand flow structures and vortices. Various capture rates were tested at specific measurement points. The study revealed that the central capture lines yielded the highest efficiency. To address air extraction from behind the exhaust duct, a back sheet panel was introduced. The results showed that installing a back sheet enhanced capture velocities. The findings contribute to understanding LEV efficiency and the importance of proper design and adjustments for effective containment of contaminants in the occupational environment.
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Data Availability Statement
Some or all data, models, or codes that support the findings of this study are available from the corresponding author upon reasonable request.
Acknowledgments
Project no. TKP2021-NKTA-34 has been implemented with the support provided by the Ministry of Innovation and Technology of Hungary from the National Research, Development, and Innovation Fund, financed under the TKP2021-NKTA funding scheme.
Author contributions: S.S. and A.K.: Conceptualization, methodology, software, validation, formal analysis, investigation, recourses, data curation, writing—original draft preparation; writing—review and editing; visualization; supervision; and funding acquisition. I.C.: Conceptualization, methodology, software, validation, formal analysis, investigation, recourses, data curation, writing—original draft preparation; writing—review and editing; visualization; supervision; project administration; and funding acquisition.
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Information & Authors
Information
Published In
Journal of Architectural Engineering
Volume 30 • Issue 2 • June 2024
Copyright
This work is made available under the terms of the Creative Commons Attribution 4.0 International license, https://creativecommons.org/licenses/by/4.0/.
History
Received: Nov 15, 2023
Accepted: Jan 24, 2024
Published online: Apr 5, 2024
Published in print: Jun 1, 2024
Discussion open until: Sep 5, 2024
ASCE Technical Topics:
- Air flow
- Architectural engineering
- Building systems
- Case studies
- Duct
- Engineering fundamentals
- Flow (fluid dynamics)
- Flow measurement
- Fluid dynamics
- Fluid mechanics
- HVAC
- Hydrologic engineering
- Laboratory tests
- Measurement (by type)
- Methodology (by type)
- Research methods (by type)
- Tests (by type)
- Turbulence
- Ventilation
- Water and water resources
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