BRITE Relaunch: A Physics-Based Simulation Model for Exploring Community Resilience to Wildfires

Regents Of The University Of Michigan - Ann Arbor, Ann Arbor MI

Investigators

Abstract

This Boosting Research Ideas for Transformative and Equitable Advances in Engineering (BRITE) Relaunch award seeks to create a predictive computational model for the ignition of buildings due to wildfires, which are a growing national threat. Structural ignition is affected by radiation from the flames as well as heat transfer from firebrands (i.e., embers). The latter has only recently gained attention in the literature despite being a leading source of structural ignitions due to wildfires. The present research seeks to formulate and validate a robust, physics-based computational model that simulates ignition from collections of firebrands on structural surfaces. The model will be informed by prior experiments on full-scale structures and structural components subjected to firebrand showers. Once the computational model is validated, it will be used to study the vulnerability of communities at the wildland-urban interface. The simulations will inform ongoing work on community resilience at the wildland-urban interface, where homeowners and policymakers are faced with (e.g., deciding what structural upgrades will have the greatest impact on community resilience). The research plan involves a model for the transport of firebrands from the wildfire using a probabilistic multiphase Eulerian approach that offers better computational efficiency and scalability for community-based simulations when compared to existing methods that focus on Lagrangian particle tracking. In addition, the approach explores the fracture and mass loss of firebrands under impact with roofs and walls using the discrete element method. This new application of the discrete element method will have significant advantages as well, including new formulations for heat and mass transfer coupled with solid mechanics. The model will be validated against prior experiments on structural components and systems. The high-fidelity computational model is expected to yield new understanding and give more accurate predictions of structural ignitions due to wildfire, leading to greater community resilience and fewer losses in the event of catastrophic wildfire. 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.