Comparison of mixing and displacement ventilation in a low energy office building during heating season

Lei Fang, Bjarne W. Olesen, Xiaozhou Wu, Fenghao Wang, Jianing Zhao

Research output: Chapter in Book/Report/Conference proceedingArticle in proceedingsResearchpeer-review

Abstract

The present study investigated the performance of mixing and displacement ventilation systems in a low energy office building during heating season. Measurements were performed with regard to air distribution and ventilation effectiveness. The results show that indoor air temperatures in occupied zone was 21.0°C for mixing ventilation and 20.8°C for displacement ventilation when supply air temperature was 19°C and air change rate was 4.2 h-. Vertical air temperature difference between the head level and the foot level were all less than 3°C and local air velocity were all less than 0.2m/s for both ventilation systems. In addition, local ventilation effectiveness ranged from 0.91 to 0.94 for mixing ventilation and from 1.03 to 1.17 for displacement ventilation. Distributions of vertical air temperature and velocity and horizontal contaminant concentration were more uniform for mixing ventilation compared to those for displacement ventilation. Due to the heat emission from equipments and occupants, heating system was not needed in the low energy office building in a mild winter. In such a situation, indoor thermal environment was still acceptable in terms of the general thermal comfort and the local thermal discomfort for a standard office worker.
Original languageEnglish
Title of host publicationProceedings of Indoor Air 2014
Publication date2014
Pages492-499
Publication statusPublished - 2014
Event13th International Conference on Indoor Air Quality and Climate - University of Hong Kong, Hong Kong, Hong Kong
Duration: 7 Jul 201412 Jul 2014
Conference number: 13
http://www.indoorair2014.org/

Conference

Conference13th International Conference on Indoor Air Quality and Climate
Number13
LocationUniversity of Hong Kong
CountryHong Kong
CityHong Kong
Period07/07/201412/07/2014
Internet address

Cite this

Fang, L., Olesen, B. W., Wu, X., Wang, F., & Zhao, J. (2014). Comparison of mixing and displacement ventilation in a low energy office building during heating season. In Proceedings of Indoor Air 2014 (pp. 492-499)