Numerical Analysis of the Effect of Fire Source Configuration on Fire-Wind Enhancement

Abstract

Detailed investigation of fire-wind interaction is highly instrumental in understanding the cause of the devastating consequences of major fire events in windy weather conditions. Enhancement of wind downstream of the fire source is a phenomenon caused by fire-wind interaction. The main objective of this study is to compare the behavior of wind enhancement for fire of either line or point sources under similar wind and heat release rate conditions. This paper uses the OpenFOAM platform as a numerical simulation tool to fundamentally investigate fire-wind enhancement phenomenon in both point and line source of the fire. A module has been developed and implemented in the FireFOAM solver to extract different components of fire-induced longitudinal and vertical forces. A new parameter expressed as an equivalent hydraulic diameter of line fire sources was introduced to represent the non-dimensional bushfire intensity. The results indicate that under the same intensity of heat release rate per unit area, enhancement of longitudinal wind in line fire is significantly higher than that of the point fire source. On the other hand, the fire-induced vertical velocity of point source fire is higher than that of the line source case.

Acknowledgments

The authors gratefully acknowledge OpenFOAM foundations for the provision of an open-source CFD platform. We also thank Dr. Yi Wang and Dr. Oluwayemisi Oluwole at FM Global Foundation for their technical advice on the validation part of this work.

Additional information

Funding

This project is funded by Australian Research Council Discovery Project grant ARC DP160103248.

Notes on contributors

Esmaeel Eftekharian

Esmaeel Eftekharian is currently a Ph.D. candidate in Infrastructure Engineering at Western Sydney University, Australia. He holds a B.Sc. degree in Mechanical Engineering, Fluid Dynamics from Shahid Bahonar University of Kerman, Iran and a M.Sc. degree in Mechanical Engineering, Energy Conversion from Shiraz University, Iran. His research interest includes computational fluid dynamics, heat transfer, and thermodynamics.

Maryam Ghodrat

Maryam Ghodrat is a research fellow and associate lecturer in the School of Engineering, Computing and Mathematics, Western Sydney University, Australia. She did her Ph.D. in Materials Sciences and Engineering at University of New South Wales, Australia. Her research interest focused on computational modeling and predictive flow behavior, thermodynamics analysis and process modeling and computational fluid dynamics simulation of fire inducing wind velocity.

Yaping He

Yaping He obtained his first engineering degree from the University of Science and Technology Beijing, China, and his Ph.D. from the University of Queensland, Australia. He served in a number of institutions and industry before joinng University of Western Sydney in 2004. He participated in the development of the Australian Fire Safety Engineering Guidelines (2nd Ed) and the International Fire Engineering Guidelines. He is a member of editorial board of two international journals.

Robert H. Ong

Robert Ong is currently a Postdoctoral Research Fellow in School of Civil Engineering at the University of Sydney, Australia. He holds a B.Eng. degree in Chemical Engineering and a Ph.D. degree in Mechanical Engineering from Curtin University, Western Australia. His research interest includes computational fluid dynamics, heat and mass transfer, and thermodynamics.

Kenny C. S. Kwok

Kenny Kwok obtained his Ph.D. in wind engineering in 1978 from Monash University, Australia. He has made significant and sustained contributions to research and professional practice in wind engineering, structural dynamics, vibration control, human perception of motion, and environmental fluid mechanics, particularly with respect to the dynamic behavior of tall buildings and flexible structures in strong winds.

Ming Zhao

Ming Zhao joined the Western Sydney University as a senior lecturer in the School of Engineering in March, 2011. He was awarded the Ph.D. degree at the State Key Laboratory of Coastal and Offshore Engineering, Dalian University of Technology, China in 2003 and worked in this laboratory as a postdoctoral fellow until 2005. He was awarded two ARC discovery grants as a chief investigator and has published over 50 refereed papers in international journals and conferences.