The effect of the strength of asymmetric heat load on indoor air quality with diffuse ceiling ventilation

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Indoor air quality has a significant effect on performance of building occupants. In this paper, indoor air quality was studied when the heat load was located asymmetrically with diffuse ceiling ventilation. The test chamber was furnished like an office room with two laptops and two monitors, a heated manikin and a heated dummy. The highest heat load was 53 W/m² and reduced to 27 W/m² in three cases. The outdoor air was supplied through diffuse ceiling. The air flow rate used was 4.8 l/s∙ m², 3.9 l/s∙m² and 2.0 l/s∙ m² in the cases of 53 W/ m², 41 W/ m² and 27 W/ m². In term of the air change efficiency, the value of efficiency varied between 50% and 54.7%. Those values of air change efficiency are slightly better than the standard mixing ventilation. The observations indicate that the highest value of the mean age of air (67.7 minutes) is for 27 W/ m² and the lowest value of the mean age of air (21.6 minutes) is for 53 W/ m². The convection flows has a significant influence on air distribution. However, air change efficiency was above 50% in every measured location and the performance of the diffused ceiling ventilation is like fully mixed ventilation.


Original languageEnglish
Title of host publicationProceedings of Roomvent & Ventilation 2018, 2-5th of June 2018, Espoo, Finland
EditorsRisto Kosonen, Mervi Ahola, Jarkko Narvanne
Publication statusPublished - 5 Jun 2018
MoE publication typeA4 Article in a conference publication
EventRoomvent & Ventilation
- Espoo, Finland
Duration: 2 Jun 20185 Jun 2018


ConferenceRoomvent & Ventilation

ID: 31198862