François-Joseph Chatelon

Physical Modeling of Surface Fire Under Nonparallel Wind and Slope Conditions

The physical model we developed in a previous work (J. H. Balbi et al., 2007) predicts fire behavior with a computational time that is faster than real time. However, it has the inconvenient of introducing an empirical law (B. J. McCaffrey, 1979), which provides flame height according to heat release rate. The authors introduce two improvements of this model: the triangular flame hypothesis and a modification taking into account the air cooling on the rear fire front. To test this variant of their simplified model, it was compared with important experimental results (D. X. Viegas, 2004b). The experiments were performed in homogeneous and plane fuel beds made with dead Pinus pinaster needles under high values of wind and slope. In spite of these high values this physical model provides a good approximation of the fire front perimeter.

Discrete event formalism to calculate acceptable safety distance

The aim of this paper is to present a dimensioning tool for fuelbreaks. It focuses on the overall approach and specifically mapping a physical model to a DEVS model, mapping a DEVS model to a DEVS service, and the client that communicates with the server. In order to assist the firefighters, we focus on a Web Service based on different software tools that can be used by firefighters to forecast fuelbreak safety zone sizes. This Web Service uses a simulation framework based on DEVS formalism, a theoretical fire spreading model developed at the University of Corsica and to display the results on a Google Map SDK. The SDK is embedded in a mobile application for touchscreen tablet. The application sends a request to our DEVS Web Service, with its geolocation, and in response receives data sets that allow to draw the safety distance.