Mechanisms of energy efficiency of supply momentum-driven stratified thermal environment with exhaust and return vents isolated by supply vent

IF 7.1 1区 工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY
Xia Zhang , Mengqi Jiang , Longxia Ma , Sheng Zhang , Zhaosong Fang , Yongjun Sun , Zhang Lin
{"title":"Mechanisms of energy efficiency of supply momentum-driven stratified thermal environment with exhaust and return vents isolated by supply vent","authors":"Xia Zhang ,&nbsp;Mengqi Jiang ,&nbsp;Longxia Ma ,&nbsp;Sheng Zhang ,&nbsp;Zhaosong Fang ,&nbsp;Yongjun Sun ,&nbsp;Zhang Lin","doi":"10.1016/j.buildenv.2024.112332","DOIUrl":null,"url":null,"abstract":"<div><div>The exhaust-return air decoupled strategy using high-temperature and low-temperature air as exhaust and return air, respectively, can effectively reduce the cooling load of the thermal buoyancy-driven stratified thermal environment. However, there is no exhaust-return air decoupled strategy for the other type of stratified thermal environments, <em>i.e.</em>, the supply momentum-driven stratified thermal environment represented by stratum ventilation. This study uses experimentally validated CFD simulations to investigate the mechanisms behind the energy efficiency of the proposed decoupled strategy for the supply momentum-driven stratified thermal environment. According to the thermal stratification characteristics of stratum ventilation, the proposed decoupled strategy positions the exhaust and return vents above and below the supply vent, respectively. The mechanisms of energy efficiency due to the decoupled strategy are revealed and compared with two typical coupled strategies of stratum ventilation (the upper coupled strategy and the lower coupled strategy with the shared vents of the exhaust and return air located above and below the supply vent, respectively). The results show that the decoupled strategy has two major mechanisms impacting energy efficiency, <em>i.e.</em>, 1) the positive mechanism lowers the return air temperature relative to the exhaust air temperature to reduce the cooling load of the return air; and 2) the negative mechanism with the upper vent drags the supply air up to the unoccupied zone, lowering air supply efficiency. With mechanism manipulation, the decoupled strategy saves energy by 30.7% and 21.3% compared with the upper and lower coupled strategies, respectively.</div></div>","PeriodicalId":9273,"journal":{"name":"Building and Environment","volume":"268 ","pages":"Article 112332"},"PeriodicalIF":7.1000,"publicationDate":"2024-11-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Building and Environment","FirstCategoryId":"5","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S0360132324011740","RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q1","JCRName":"CONSTRUCTION & BUILDING TECHNOLOGY","Score":null,"Total":0}
引用次数: 0

Abstract

The exhaust-return air decoupled strategy using high-temperature and low-temperature air as exhaust and return air, respectively, can effectively reduce the cooling load of the thermal buoyancy-driven stratified thermal environment. However, there is no exhaust-return air decoupled strategy for the other type of stratified thermal environments, i.e., the supply momentum-driven stratified thermal environment represented by stratum ventilation. This study uses experimentally validated CFD simulations to investigate the mechanisms behind the energy efficiency of the proposed decoupled strategy for the supply momentum-driven stratified thermal environment. According to the thermal stratification characteristics of stratum ventilation, the proposed decoupled strategy positions the exhaust and return vents above and below the supply vent, respectively. The mechanisms of energy efficiency due to the decoupled strategy are revealed and compared with two typical coupled strategies of stratum ventilation (the upper coupled strategy and the lower coupled strategy with the shared vents of the exhaust and return air located above and below the supply vent, respectively). The results show that the decoupled strategy has two major mechanisms impacting energy efficiency, i.e., 1) the positive mechanism lowers the return air temperature relative to the exhaust air temperature to reduce the cooling load of the return air; and 2) the negative mechanism with the upper vent drags the supply air up to the unoccupied zone, lowering air supply efficiency. With mechanism manipulation, the decoupled strategy saves energy by 30.7% and 21.3% compared with the upper and lower coupled strategies, respectively.
求助全文
约1分钟内获得全文 求助全文
来源期刊
Building and Environment
Building and Environment 工程技术-工程:环境
CiteScore
12.50
自引率
23.00%
发文量
1130
审稿时长
27 days
期刊介绍: Building and Environment, an international journal, is dedicated to publishing original research papers, comprehensive review articles, editorials, and short communications in the fields of building science, urban physics, and human interaction with the indoor and outdoor built environment. The journal emphasizes innovative technologies and knowledge verified through measurement and analysis. It covers environmental performance across various spatial scales, from cities and communities to buildings and systems, fostering collaborative, multi-disciplinary research with broader significance.
×
引用
GB/T 7714-2015
复制
MLA
复制
APA
复制
导出至
BibTeX EndNote RefMan NoteFirst NoteExpress
×
提示
您的信息不完整,为了账户安全,请先补充。
现在去补充
×
提示
您因"违规操作"
具体请查看互助需知
我知道了
×
提示
确定
请完成安全验证×
copy
已复制链接
快去分享给好友吧!
我知道了
右上角分享
点击右上角分享
0
联系我们:info@booksci.cn Book学术提供免费学术资源搜索服务,方便国内外学者检索中英文文献。致力于提供最便捷和优质的服务体验。 Copyright © 2023 布克学术 All rights reserved.
京ICP备2023020795号-1
ghs 京公网安备 11010802042870号
Book学术文献互助
Book学术文献互助群
群 号:481959085
Book学术官方微信