Computer Program for Calculating and Plotting Fire Direction and Rate of Spread

摘要

An algorithm has been developed for calculating the direction and rate of spread of a fire across a triangular plot (Simard et al. 1984). Data required are the times of arrival of the fire at any three points (which form the three corners of a triangle), the length of the two sides adjacent to the fire's first arrival point, and the included angle. A program has been written to perform the calculations on a TI-59 hand-held calculator (Eenigenburg 1983). In the paper, the authors extend the computational procedures to allow plots with more than three time measurement points. By comparing the rates and directions derived from each triangle formed from four or more points taken three at a time, the authors can evaluate the uniformity of fire spread across the plot.