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International Journal of Wildland Fire International Journal of Wildland Fire Society
Journal of the International Association of Wildland Fire
RESEARCH ARTICLE

Firebrand transport from a novel firebrand generator: numerical simulation of laboratory experiments

R. Wadhwani A B , D. Sutherland B C , A. Ooi B D and K. Moinuddin A B *
+ Author Affiliations
- Author Affiliations

A Centre for Environmental Safety and Risk Engineering, Victoria University, Melbourne, Vic. 3030, Australia.

B Bushfire and Natural Hazards Cooperative Research Centre (CRC), Melbourne, Vic. 3002, Australia.

C School of Science, University of New South Wales, Canberra, ACT 2600, Australia.

D Department of Mechanical Engineering, University of Melbourne, Vic. 3052, Australia.

* Correspondence to: khalid.moinuddin@vu.edu.au

International Journal of Wildland Fire 31(6) 634-648 https://doi.org/10.1071/WF21088
Submitted: 18 June 2021  Accepted: 13 April 2022   Published: 13 May 2022

© 2022 The Author(s) (or their employer(s)). Published by CSIRO Publishing on behalf of IAWF.

Abstract

Firebrands (often called embers) increase the propagation rate of wildfires and often cause the ignition and destruction of houses. Predicting the motion of firebrands and the ignition of new fires is therefore of significant interest to fire authorities. Numerical models have the potential to accurately predict firebrand transport. The present study focuses on conducting a set of benchmark experiments using a novel firebrand generator, a device that produces controlled and repeatable sets of firebrands, and validating a numerical model for firebrand transport against this set of experiments. The validation is conducted for the transport of non-burning and burning cubiform firebrand particles at two flow speeds. Four generic drag sub-models used to estimate drag coefficients that are suited for a wide variety of firebrand shapes are verified for their applicability to firebrand transport modelling. The four sub-models are found to be good in various degrees at predicting the transport of firebrand particles.

Keywords: contour, contour peak location, drag models, embers, Fire Dynamics Simulator, firebrand generator, Lagrangian particles, lateral spread, short-range firebrands.


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