CUED Publications database

Ventilation effectiveness measures based on heat removal: Part 2. Application to natural ventilation flows

Coffey, CJ and Hunt, GR (2007) Ventilation effectiveness measures based on heat removal: Part 2. Application to natural ventilation flows. Building and Environment, 42. pp. 2249-2262. ISSN 0360-1323

Full text not available from this repository.

Abstract

The three effectiveness measures based on the ability of a flow to flush buoyancy from a ventilated space proposed by Coffey and Hunt [Ventilation effectiveness measures based on heat removal-part 1. Definitions. Building and Environment, in press, doi:10.1016/j.buildenv.2006.03.016.] are applied to assess and compare two fundamental natural ventilation flows. We focus on the limiting cases of passive displacement and passive mixing ventilation flows during transient conditions. These transient flows occur when, for example, heat is purged from a building at night. Whilst it is widely recognised that mixing flows are less efficient at purging heat than displacement flows, our results indicate that, when a particular zone of a room is considered, displacement ventilation can result in lower effectiveness than mixing ventilation. When a room is considered as a whole, displacement ventilation yields higher effectiveness than mixing ventilation and we quantify these differences in terms of the geometry of the space and opening area. The proposed theoretical predictions are compared with effectiveness deduced from measurements made during laboratory experiments and show good agreement. © 2006 Elsevier Ltd. All rights reserved.

Item Type: Article
Uncontrolled Keywords: Buoyancy removal Passive displacement Passive mixing Transient flows Ventilation effectiveness
Subjects: UNSPECIFIED
Divisions: Div A > Fluid Mechanics
Depositing User: Cron Job
Date Deposited: 07 Mar 2014 11:26
Last Modified: 08 Dec 2014 02:31
DOI: 10.1016/j.buildenv.2006.03.015