Paper 7
Simulation of Atrium Smoke Filling by Computational
Fluid Dynamics
C.L.
Chow1 and S.S. Han2
1Department
of Architecture, The Martin Centre for Architectural and Urban Studies,
University of Cambridge, UK
2Research
Centre for Fire Engineering, Department of Building Services Engineering,
The Hong Kong Polytechnic University, Hong Kong, China
Abstract
Computational Fluid Dynamics (CFD) is evidently relevant to the study
of fires, yet the intermediate chemistry has yet to be factored
successfully into combustion models. Consequently, predicted airflow
patterns, together with pressure and temperature contours, are mostly used
in evaluating the performance of smoke control systems. But even using
these assumptions, very few studies exist comparing predicted results from
CFD with experimental findings. This leaves research with a paucity of
data on how smoke is likely to spread, fill and be controlled in large
halls.
While hot smoke tests in a hall in Japan have yielded good-quality
experimental data for smoke layer interface heights, the dominant approach
to hazard assessment on big projects in East Asia is to use a software
Fire Dynamics Simulator (FDS) developed at the National Institute of
Standards and Technology in the USA. In this paper, FDS predicted results
for smoke filling and exhaust will be examined side-by-side with
experimental data. Our technique is to compare recorded transient smoke
layer interface heights with the results predicted by FDS.
This work also responds to questions on how to determine smoke layer
interface height. In addition to the default FDS method (FDS menu), two
methods are proposed to determine heights from sharp changes in,
respectively, vertical temperature profiles and particle tracking.
Functional analysis is applied to justify predictions, with results
suggesting that CFD offers fairly good predictions on smoke layer
interface height.
Key words: Computational Fluid Dynamics, atrium, smoke filling,
smoke layer interface height.
References
Chow WK: (1995) "Use of computational fluid dynamics for
simulating enclosure fires", Journal of Fire Sciences. 13, (4),
pp300-334.
Chow WK: (2008) "Thermal engineering tools in performance-based
design for fire safety", Heat Transfer Engineering. 29, (9),
pp757-762.
Chow WK and Zou GW (2009) "Numerical simulation of pressure
changes in closed chamber fires", Building and Environment. 44, (6),
pp1261-1275.
Chow WK, Li SS, Gao Y and Chow CL: (2009) "Numerical studies on
atrium smoke movement and control with validation by field tests",
Building and Environment. 44, (6), pp1150-1155.
He Y, Fernando A, Luo MC: (1998) "Determination of interface
height from measured parameter profile in enclosure fire experiment",
Fire Safety Journal. 31, (1), pp19-38.
Klote JH and Milke JA: (1992) "Design of Smoke Management
Systems", American Society of Heating, Refrigerating and Air
Conditioning Engineers, Inc. Atlanta, Ga., USA; Society of Fire Protection
Engineers, Boston, MA, USA.
Liu FS, Guo HS and Smallwood GJ; (2004) "Effects of radiation
model on the modeling of a laminar coflow methane/air diffusion
flame", Combustion and Flame. 138, (1-2), pp136-154.
McGrattan K, Klein B, Hostikka S and Floyd J (2008a) "Fire
Dynamics Simulator (Version 5) User's Guide", NIST Special
Publication 1019-5, National Institute of Standards and Technology, US
Department of Commerce, USA, January.
McGrattan K, Hostikka S, Floyd J, Baum H, Rehm R, Mell W and McDermott
R: (2008b) "Fire Dynamics Simulator (Version 4) - Technical Reference
Guide", NIST Special Publication 1018, National Institute of
Standards and Technology, US Department of Commerce, USA, October.
Mok WK and Chow WK: (2004) "'Verification and validation' in
modeling fire by computational fluid dynamics", International Journal
on Architectural Science. 5, (3), pp58-67.
National Fire Protection Association: (2000) "NFPA 92B-2000 Guide
for Smoke Management Systems in Malls, Atria, and Large Areas",
National Fire Protection Association, Quincy, Mass., USA.
Peacock RD, Reneke PA, Davis WD and Jones WW: (1999) "Quantifying
fire model evaluation using function analysis", Fire Safety Journal.
33, pp167-184.
US Nuclear Regulatory Commission. "Verification and Validation of
Selected Fire Models for Nuclear Power Plant Applications (NUREG-1824,
Vols. 1-7) - Draft Report for Comment, US Nuclear Regulatory Commission
plans",
http://www.nrc.gov/reading-rm/doc-collections/ nuregs/staff/sr1824, 2008.
Yamana T and Tanaka T: (1985) "Smoke control in large scale
spaces, Part 2: Smoke control experiments in large scale spaces",
Fire Science and Technology. 5, (1), pp41-54.
Yin R and Chow WK: (2002) "Building fire simulation with a field
model based on large eddy simulation", Architectural Science Review.
45, (2), pp145-153.
|
