Effects of Terrain Geometry Processing Methods on Fire Spread in Wildland Fire Modeling

This study was conducted to understand the characteristics of wildfire spread according to the processing methods of terrain geometry in the computational domain based on topographic data. The terrain geometry of the computational domain was handled using body-fitted (BF) grids and the cut-cell method (CCM), and the spread of the wildfire was simulated using a level-set model incorporating the heat release rate. The fire spread predicted by the BF grid and CCM showed similar overall trends despite local differences. A simple model was proposed to estimate the perimeter of the fireline based on the calculated heat release rate with fire spread, which showed good agreement with the field results predicted by the level-set method. The cut-cell method can enhance the applicability of wildland fire-spread models due to its ease of handling complex terrain geometry and reasonable agreement with the BF grid.