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Title: A numerical study on the effects of exhaust locations on energy consumption and thermal environment in an office room served by displacement ventilation
Authors: Ahmed, Ahmed Qasim
Gao, Shian
Kareem, Ali Khaleel
First Published: 22-Mar-2016
Publisher: Elsevier
Citation: Energy Conversion and Management, 2016, 117, pp. 74-85
Abstract: In an office room, many factors affect the pattern of airflow, thermal comfort, indoor air quality and energy saving. In this study, the effects of the location of exhaust diffusers where the warm and contaminant air is extracted and their relation to room heat sources on thermal comfort and energy saving were investigated numerically for an office served by a displacement ventilation system. The indoor air quality in the breathing level and the inhaled zone were also evaluated. The contaminants were released from window and door frames in order to simulate the contaminants coming from outside. The amount of energy consumption and the indoor thermal environment for various exhaust locations were investigated numerically using the computational fluid dynamics techniques. The results showed that the thermal indoor environment, thermal comfort, quality of indoor air and energy saving were greatly improved by combining the exhaust outlets with some of the room’s heat sources such as ceiling lamps and external walls. In particular, a 25.0% of energy saving was achieved by combining the exhaust diffuser with room’s ceiling lamps. In addition, locating the exhaust diffuser near the heat sources also reduced the cooling coil load by 13.8%. The risk of a large difference in temperature between the head and foot levels, increased particle concentration in the occupied zone, as well as increased energy consumption was also clearly demonstrated when the exhaust and recirculated air outlet (return opening) were combined in one unit in the occupied boundary area that is located at 2 m away from the occupants. Thus, for the optimum energy saving and better indoor environment, the combination of the indoor heat sources with the exhaust outlet is necessary.
DOI Link: 10.1016/j.enconman.2016.03.004
ISSN: 0196-8904
Version: Post-print
Status: Peer-reviewed
Type: Journal Article
Rights: Copyright © Elsevier 2016. After embargo this will be an open-access article distributed under the terms of the Creative Commons Attribution-Non Commercial-No Derivatives License (, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are made.
Description: The file associated with this record is under a 24 month embargo from publication in accordance with the publisher's self-archiving policy. The full text may be available through the publisher links provided above.
Appears in Collections:Published Articles, Dept. of Engineering

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