Investigation of Fire Propagation using Discrete Tree Simulations

Handeul Son

2021

Joe Theiss '19 simulated the fire propagation with discrete trees using Python and determined 𝑣π‘₯ increases if π‘‡β„Ž and 𝑆𝑙 increases but decreases if 𝑇𝑑 increases. Since the Python code made by Joe Theiss '19 was difficult to use due to the lack of explanations, annotations in the whole code were made.

The values of 𝑣π‘₯ were computed in the range of 1 pixel ≀ 𝑇𝑑 ≀ 8 pixels, 20 pixels ≀ π‘‡β„Ž ≀50 pixels, and βˆ’45Β° ≀ 𝑆𝑙 ≀ 45Β° to examine how 𝑆𝑙, π‘‡β„Ž, and 𝑇𝑑 affect 𝑣π‘₯ and which factor alters 𝑣π‘₯ the most. Td was identified to be the most important variable, with a clear inverse relationship following 𝑣π‘₯=(35.9Β±0.1)βˆ™π‘‡π‘‘(βˆ’1.055Β±0.003) pixels/second. π‘‡β„Ž and 𝑆𝑙 were identified to affect the acceleration, while 𝑇𝑑 was identified to affect the initial speed. Since the effect on initial speed varied 𝑣π‘₯ from 3 pixels/second to 33 pixels/second while the effect on acceleration varied 𝑣π‘₯ from 4 pixels/second to 8 pixels/second, the effect on initial speed was stronger and it was the reason why 𝑇𝑑 was the most important variable.

It was exciting to investigate large amount of 𝑣π‘₯values and determine the relationship with a specific equation. The wind effect on 𝑣π‘₯ can be simulated in the further research because wind strongly affects 𝑣π‘₯ in nature.