Analysis of a Wildfire and Smoke Propagation Model at Chiak Mountain Using Computational Fluid Dynamics

Abstract

This study analyzed the arrival time and diffusion pattern of a wildfire at Chiak Mountain, Wonju, Korea. Simcenter STAR-CCM+, which is a computational fluid dynamics program, was used to analyze flow fields generated by mountain topography and to create a combustion model. The size of the area under study was 16 km², and ignition was conducted at the first campsite. Approximately six million mesh were generated. The temperature and propagation of soot were analyzed for 1 h after the simulation was started. Implicit unsteady analysis was used for time-dependent diffusion, and molecular diffusivity was used for flow field analysis. The results were as follows. 1) The spread of the wildfire was affected by the stack effect derived from the wind direction and mountain topography. 2) Approximately 22 min were required for the wildfire to spread from the campground to a western point 500 m away, and the average temperature was 1,200 ℃ or higher. 3) The spread of the wildfire and soot caused by the difference between the ignition and flash points of the wildfire became faster over time.