EAGER: Establishing a Numerical Framework for Multi-scale Simulations of Wildfire Spread and Smoke Dispersion

University Of Texas At Dallas, Richardson TX

Investigators

Abstract

Many communities across the country live under the threat of wildland fires that can cause devastating safety, health and financial risks. Computational models of wildfire spread have become a critical tool for the development of prevention plans and containment strategies. Current models provide general forecast of the evolution of fire perimeters. However, these models often have limitations in predicting extreme fire events due to the interaction of weather, topography and turbulence. The proposed work aims at overcoming these limitations by developing a simulation framework with an unprecedented level of resolution and accuracy. The goal is to provide a comprehensive and detailed description of wildfire evolution. Use of improved computer models will help mitigate the risk and harm of wildland fires, thus enhancing the national welfare and security. Wind and terrain slope are major factors that affect wildfire and smoke spread. These interactions occur over a wide range of spatial and temporal scales. To account for the complexity of the phenomena, in this project a numerical weather prediction (NWP) model will be coupled with a computational code based on large-eddy simulation (LES). The code scales efficiently for parallel computation. The topography will be included in the numerical simulations with the efficient immersed boundary method. The evolution of the fire perimeter will be computed by a fire-spread simulator and tracked with the level-set method. The proposed approach will permit the simulation of wildfire evolution under realistic wind patterns, which account for the interaction with the burning fuel, large-scale atmospheric circulation, and local terrain features. This project will be focused on the influence of topography and small-scale flow features on the evolution of wildland fires. It will also address how to downscale the atmospheric circulation from NWP to the high resolution LES domain. This is still an open problem in atmospheric science, which has great relevance in several other fields. The goals of the project include evaluating the optimal setup for simulation and assess the feasibility of the numerical framework for real time tracking of fire spread. Additionally, the numerical results will provide a valuable dataset to refine and develop reduced-order models for wildfire spread and smoke dispersion. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.