Influence of slope on propagating fire fronts
Niklas Manz
The idea of exploring the dynamics of wildfires (forest fires) with an array of matches was first published
In 2015 [C. Punckt, P. S. Bodega, P. Kaira, and H. H. Rotermund, Wildfires in the lab: Simple experiment and models for the exploration of excitable dynamics, J. Chem. Educ., 92(8), 13301337, 2015].
In the article, the authors explained and simulated some propagation conditions. We plan to continue Robin Morillo’s Junior IS (Spring 2016) and Senior IS (Fall 2016 – Spring 2017) results.
One of the results is shown in the following graph. His experimental data points (front velocity vs. slope angle) are plotted with two different fitting conditions: A linear (solid blue line) and the tangentsquared relationship (dotted green line) as used in the Rothermel model (R. C. Rothermel, A mathematical model for predicting the spread in wildland fuels, USDA Forest Service, 1972, Research paper INT115, Ogden, Utah, USA, 40 p.). The red vertical lines indicate the (current) thresholds for possible fire fronts.
Projects

Sloped Experiments: Effect of a wildfire propagating up or down an incline. Robin Morillo’s experiments brought already interesting results which should be explored in more detail.

Sloped Simulations: We use a Cellular Automata Model in Matlab to simulate fire front behavior under sloped conditions. Besides planar/straight fronts, we are investigating the influence of i) the slope on fire spirals and ii) the inhomogeneity of the matches on the shape of fire fronts. A further step would be to investigate the influence of varying slopes – as in real mountainous environment.

Planar Fire spirals: Another exciting aspect could be to create fire spirals, which got simulated in the article but not experimentally achieved. We can build a setup with sustained excitabilities and defined refractory phases (using flammable liquid and some kind of wicks with specific diffusion conditions for the fluid).
Presented Poster Research Links