Optimization on emergency longitudinal ventilation design

Research output: Chapters, Conference Papers, Creative and Literary WorksRGC 32 - Refereed conference paper (with host publication)peer-review

View graph of relations

Author(s)

Detail(s)

Original languageEnglish
Title of host publicationAIP Conference Proceedings
PublisherAIP Publishing LLC
Pages812-817
Volume1233
ISBN (print)978-0-7354-0778-7
Publication statusPublished - Nov 2009

Conference

Title2nd International Symposium on Computational Mechanics (ISCM II) and the 12th International Conference on the Enhancement and Promotion of Computational Methods in Engineering and Science ( EPMESC XII)
PlaceChina
CityHong Kong, Macau
Period30 November - 3 December 2009

Abstract

Emergency ventilation design in longitudinally ventilated vehicular tunnels is vital to provide safe egress route for tunnel user under fire situations. In this study, the influences of the location of active fan groups on the upstream velocity are investigated using Computational Fluid Dynamics (CFD) techniques. The numeric model was firstly validated again the experimental data from Memorial Tunnel Fire Ventilation Test Program (MTFVTP). Based on the validated model, parametric studies were then preformed attempting to establish a semi-empirical correlation between the location of fan groups and the upstream velocity. In the presence of solid fire, it was found that the buoyant force by the fire source and inertial force by the fans interact with each other and resulted in a "leveling-off" characteristic when the inertial force is no longer dominating. Such interaction re-distributed the ventilation flow direction and sequentially reduces the magnitude of the upstream velocity. In other word, the industrial practice of activating furthest fan group may not be able to prevent the backlayering as a consequence of solid fires. Fans closer to the fire source are recommended to be activated for preventing the hazard of backlayering. Furthermore, through the parametric study, location of ventilation fans is found to have significant effect on the upstream velocity. Such finding suggests that other geometrical parameters could also impose adverse effects to the ventilation system. Existing empirical equation could be insufficient to cover all possible ventilation design scenarios.

Research Area(s)

  • CFD, Longitudinal ventilation, Optimization, Tunnel Fire

Bibliographic Note

Full text of this publication does not contain sufficient affiliation information. With consent from the author(s) concerned, the Research Unit(s) information for this record is based on the existing academic department affiliation of the author(s).

Citation Format(s)

Optimization on emergency longitudinal ventilation design. / Se, Camby M. K.; Yuen, Richard K. K.; Cheung, Sherman C. P. et al.
AIP Conference Proceedings. Vol. 1233 AIP Publishing LLC, 2009. p. 812-817.

Research output: Chapters, Conference Papers, Creative and Literary WorksRGC 32 - Refereed conference paper (with host publication)peer-review