Hostname: page-component-8448b6f56d-42gr6 Total loading time: 0 Render date: 2024-04-18T09:34:59.804Z Has data issue: false hasContentIssue false

Fire whirls due to surrounding flame sources and the influence of the rotation speed on the flame height

Published online by Cambridge University Press:  04 July 2007

RUI ZHOU
Affiliation:
Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
ZI-NIU WU*
Affiliation:
Department of Engineering Mechanics, Tsinghua University, Beijing 100084, China
*
Author to whom correspondence should be addressed: ziniuwu@tsinghua.edu.cn

Abstract

In this paper, we use numerical simulation and laboratory experimental observation to show that fire whirls can be generated spontaneously through the interaction between a central flame and surrounding organized or randomly distributed flames. The momentum of the air stream entrained by the main flame decreases as it crosses a surrounding flame, so that the main flame rotates if surrounding flames are arranged in such a way as to block the passage of the air stream directed towards the centre of the main flame and to favour flows in a particular circumferential direction. An analysis is performed to study the role of the rotation speed in the flame height. It is found that the flame height initially decreases to a minimum owing to the inflow boundary layer wind reducing the initial vertical velocity of gas for low rotation speed and to entrainment enhancement reducing the rising time, and then it increases owing to the pressure reduction at the centre of the rotating vortex and entrainment suppression extending the rising time.

Type
Papers
Copyright
Copyright © Cambridge University Press 2007

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

Atobiloye, R. Z. & Britter, R. E. 1994 On flame propagation along vortex tubes. Combust. Flame 98, 220230.CrossRefGoogle Scholar
Battaglia, F., McGrattan, K. B., Rhem, R. G & Baum, H. R. 2000a Simulating fire whirls. Combust. Theory Model. 4, 123138.CrossRefGoogle Scholar
Battaglia, F., Rehm, R. G. & Baum, H. R. 2000b The fluid mechanics of fire whirls: An inviscid model. Phys. Fluids 12, 28592867.CrossRefGoogle Scholar
Chigier, N. A., Beer, J. M., Grecov, D. & Bassindale, K. 1970 Jet flames in rotating flow fields. Combust. Flame 14, 171180.CrossRefGoogle Scholar
Chow, W. K. & Yin, R. 2004 A new model on simulating smoke transport with computational fluid dynamics. Building Environ. 39, 611620.CrossRefGoogle Scholar
Chow, W. K. & Zou, G. W. 2005 Correlation equations on fire-induced air flow rates through doorway derived by large eddy simulation. Building Environ. 40, 897906.CrossRefGoogle Scholar
Christensen, A. M. & Icove, D. J. 2004 The application of nist's fire dynamics simulator to the investigation of carbon monoxide exposure in the deaths of three pittsburgh fire fighters. J. Forensic Sci. 49, 104107.CrossRefGoogle Scholar
Emmons, H. W. & Ying, S. J. 1967 The fire whirl. In Proc. 11th Int. Symp. Combustion, pp. 475488. Combustion Institute, Pittsburgh, PA.Google Scholar
Farouk, B., McGrattan, K. B. & Rehm, R. G. 2000 Large eddy simulation of naturally induced fire whirls in a vertical square channel with corner gaps. ASME Heat Transfer Div Publ HTD 366, 7380.Google Scholar
Graham, H. E. 1952 A fire-whirlwind of tornadic violence. Fire Control Notes 13, 2224.Google Scholar
Graham, H. E. 1957 Fire whirlwind formation as favored by topography and upper winds. Fire Control Notes 18, 2024.Google Scholar
McGrattan, K. B. 2004 Fire dynamics simulator (version 4) “c technical reference guide. Tech. Rep. 1018. National Institute of Standards and Technology, special Publication.Google Scholar
Meroney, R. N. 2003 a Fire whirls and building aerodynamics. In Proc. 11th Int. Conf. on Wind Engineering.Google Scholar
Meroney, R. N. 2003 b Fire whirls, fire tornadoes, and fire storms: Physical and numerical modeling. In Proc. PHYSMOD'03: Intl. Workshop on Physical Modelling of Flow and Dispersion Phenomena.Google Scholar
Meroney, R. N. 2004 Fires in porous media: Natural and urban canopies. In NATO Advanced Study Institute on Flow and Transport Processes in Complex Obstructed Geometries: From Cities and Vegetative Canopies to Industrial Problems. ASME.Google Scholar
Ryder, N. L., Schemel, C. F. & Jankiewicz, S. P. 2006 Near and far field contamination modeling in a large scale enclosure: Fire dynamics simulator comparisons with measured observations. J. Hazard. Mater. 130, 182186.CrossRefGoogle Scholar
Ryder, N. L., Sutula, J. A., Schemel, C. F., Hamer, A. J. & VanBrunt, V. Brunt, V. 2004 Consequence modeling using the fire dynamics simulator. J. Hazard. Mater. 115, 149154.CrossRefGoogle ScholarPubMed
Satoh, K. & Yang, K. T. 1996 Experimental observations of swirling fires. In Proc. 1996 ASME Intl. Mechanical Engineering Congress and Exposition. Part 1, pp. 393400. ASME.Google Scholar
Satoh, K., Zhu, J. P., Liu, N. & Yang, K. T. 2005 Experiments and analysis of interaction among multiple fires in equidistant fire arrays. In Proc. ASME Summer Heat Transfer Conf. Elsevier (in press).Google Scholar
Yi, L., Chow, W. K., Li, Y. Z. & Huo, R. 2005 A simple two-layer zone model on mechanical exhaust in an atrium. Building Environ. 40, 869880.CrossRefGoogle Scholar
Supplementary material: PDF

Zhou and Wu Supplementary Appendix

Appendix.pdf

Download Zhou and Wu Supplementary Appendix(PDF)
PDF 104.6 KB