International Journal of Applied Science and Engineering

Published by Chaoyang University of Technology

Ahmed Qasim Ahmed*, Ahmed Jawad Khaleel, H. J Dakkama, Wisam A. M. Al-Shohani

Middle Technical University, Technical Engineering College-Baghdad, Baghdad, Iraq


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Energy saving and indoor thermal environment are affected by many factors such as room direction, internal heat sources and outlet locations. In this paper, the novel method for reducing the effect of heat transfer from the external wall to the office room was presented. In this method, the effect of using a new heat extract slot (HES) system behind the external wall inside the office room and its relation to the amount of extracted air on both energy demand and indoor thermal environment were studied numerically. The proposed system was installed on the external wall which exposures to a high amount of heat. In order to show the performance of using the novel system, four different amounts of extract air, from the exit and HES system were investigated numerically by using the validated CFD model. The result revealed that by using the proposed HES system, a significant enhancement of the energy saving and indoor thermal comfort were achieved. In particular, up to 57% of energy saving with an acceptable thermal comfort were achieved when only the HES system activated an extracted outlet in the room (20% of exhaust air). Thus, 20% of the exhaust air is the optimum rate of the HES system regarding energy saving and thermal comfort. This will give a significant reduction in energy demand by the cooling coil and enhancing the indoor thermal environment.

Keywords: Displacement ventilation, Local extraction, CFD, Energy saving, Thermal comfort.

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Received: 2021-06-09
Revised: 2021-10-09
Accepted: 2021-10-19
Publication Date: 2021-12-01

Cite this article:

Ahmed, A.Q., Khaleel, A.J., Dakkama, H.J., Al-Shohani, W.A.M. 2021. Energy saving and indoor thermal comfort enhancement by using a novel heat extract slot system installed on external room wall. International Journal of Applied Science and Engineering, 18, 2021191.

  Copyright The Author(s). This is an open access article distributed under the terms of the Creative Commons Attribution License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are cited.

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