Published works

Background; Junction fires occur when two fire fronts merge. The ROS and HRR of the junction quickly increase more than that of each fire front; this effect is exacerbated by slopes. Aims; Numerical modelling of junction fires and an interpretation of their behaviour is given by examining the key factors that influence the fires. Methods; Physics-based simulations of laboratory-scale junction fires were performed for shrub fuel bed using FIRESTAR3D. Twenty cases were simulated to quantify the effect of slope (0° to 40°) and junction angles (15° to 90°). Key results; Accelerative and decelerative behaviours were observed for junction angles lower than 45°, but above this, deceleration was absent. The behaviour was firmly related to junction angle evolution which controlled the flame and the interactions between fire fronts. HRR followed similar trends; maximum HRR increased with increasing junction angle. Convection was found to be the primary heat transfer mode in the initial propagation phase. In non-slope cases, radiation was the dominant method of heat transfer, but convection dominated fires on slopes. Conclusions; The physics-based model provided great insight into junction fire behaviour. The junction angle was critical for determining ROS and fire behaviour. Implications; The research helped to assess the effects of some topographical parameters in extreme fires. Situational awareness, operational predictions, and firefighter safety will consequently improve.