Numerical analysis of the effect of fire source configuration on fire-wind enhancement

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.