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Title: Micro-environmental control for efficient local cooling

Abstract

Micro-environment is hereby defined as the air space and environment around a person that directly impacts his/her thermal sensation. Most existing HVAC systems condition the air of the entire room including the unoccupied space, which leaves a big potential to save energy. This study aims at evaluating the performance of three existing air terminal devices (ATDs) to locally remove enough heat from the micro-environment to manage the thermal balance so as not to sacrifice thermal comfort when the ambient unoccupied space temperature is increased by 2.2 °C from 23.9 °C to 26.1 °C in the summer to reduce the external cooling load. A computational fluid dynamics (CFD) model was developed, validated by full-scale chamber tests and applied to evaluate different configurations of the ATDs for local cooling. Results show that the predicted performance agreed well with the measurements, and the selected ATD, with only 50 W cooling power, was always able to remove a sufficient amount of heat from the microenvironment in a room of raised temperature, when the manikin was moved inside a semicircle movement range. The cooling performance of the jet was increased more by increasing the supply air flow rate than reducing the supply temperature and wasmore » highly dependent on the shooting angle. Finally, the heat flux from the manikin surface is very sensitive to the surface temperature and furniture placement, and proper specification of the surface temperature is crucial for the CFD simulation to match the measured results.« less

Authors:
; ; ;
Publication Date:
Research Org.:
Syracuse Univ., Syracuse, NY (United States)
Sponsoring Org.:
USDOE Advanced Research Projects Agency - Energy (ARPA-E)
OSTI Identifier:
1349652
Grant/Contract Number:
AR0000526
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Building and Environment
Additional Journal Information:
Journal Volume: 118; Journal Issue: C; Journal ID: ISSN 0360-1323
Publisher:
Elsevier
Country of Publication:
United States
Language:
English
Subject:
32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATION; micro-environment; thermal balance; CFD; local cooling

Citation Formats

Kong, Meng, Dang, Thong Q., Zhang, Jianshun, and Khalifa, H. Ezzat. Micro-environmental control for efficient local cooling. United States: N. p., 2017. Web. doi:10.1016/j.buildenv.2017.03.040.
Kong, Meng, Dang, Thong Q., Zhang, Jianshun, & Khalifa, H. Ezzat. Micro-environmental control for efficient local cooling. United States. doi:10.1016/j.buildenv.2017.03.040.
Kong, Meng, Dang, Thong Q., Zhang, Jianshun, and Khalifa, H. Ezzat. 2017. "Micro-environmental control for efficient local cooling". United States. doi:10.1016/j.buildenv.2017.03.040.
@article{osti_1349652,
title = {Micro-environmental control for efficient local cooling},
author = {Kong, Meng and Dang, Thong Q. and Zhang, Jianshun and Khalifa, H. Ezzat},
abstractNote = {Micro-environment is hereby defined as the air space and environment around a person that directly impacts his/her thermal sensation. Most existing HVAC systems condition the air of the entire room including the unoccupied space, which leaves a big potential to save energy. This study aims at evaluating the performance of three existing air terminal devices (ATDs) to locally remove enough heat from the micro-environment to manage the thermal balance so as not to sacrifice thermal comfort when the ambient unoccupied space temperature is increased by 2.2 °C from 23.9 °C to 26.1 °C in the summer to reduce the external cooling load. A computational fluid dynamics (CFD) model was developed, validated by full-scale chamber tests and applied to evaluate different configurations of the ATDs for local cooling. Results show that the predicted performance agreed well with the measurements, and the selected ATD, with only 50 W cooling power, was always able to remove a sufficient amount of heat from the microenvironment in a room of raised temperature, when the manikin was moved inside a semicircle movement range. The cooling performance of the jet was increased more by increasing the supply air flow rate than reducing the supply temperature and was highly dependent on the shooting angle. Finally, the heat flux from the manikin surface is very sensitive to the surface temperature and furniture placement, and proper specification of the surface temperature is crucial for the CFD simulation to match the measured results.},
doi = {10.1016/j.buildenv.2017.03.040},
journal = {Building and Environment},
number = C,
volume = 118,
place = {United States},
year = 2017,
month = 6
}

Journal Article:
Free Publicly Available Full Text
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