
The original goal of this program was to create a model that attempted to
accurately model fire flow. This year’s goal was to improve upon the
previous year’s progress. The team achieved great success in more accurately
modeling the spread of fire by incorporating concepts from Huygen’s
Principle along with many other fire-spread models. Historically, fires cause
more damage every year than any other natural disaster. When attempting to
model fire, several important factors must be considered in order to project
for realistic fire flow. These factors include spread rates over different
fuels and heat’s effect on fire, as fire acceleration, wind, elevation,
moisture contents, amounts of fuel, spot fires, and crown fires. However,
accounting for all these variables requires an extremely complex model. Therefore,
this project concentrates on the basis of fire flow in two dimensions limiting
its factors to what was verifiable.
In building this year’s model, rather than just modeling heat flow to
demonstrate the advance of a fire as was done last year, both fire flow and
heat flow have been differentiated to more realistically show a fire’s
expansion perimeter. The most important aspect of heat generated by a fire
is the possibility that heat could lead to the rapid acceleration of a fires
perimeter. The basis of the fire flow process is the Elliptical Fire Theory,
which simply states that fire will form a perfect circle under perfect conditions.
The fire flow process involves locating the fire’s perimeter and extending
new fire ellipses. The determining factor which establishes fire flow is the
varying degrees of spread rates of the virtual-forest fuels. In the program,
heat flow is accounted for using Newton’s Law of Cooling, the Stefan
Boltzmann Law of Radiation, and Fourier’s Law of Conduction.
The environment also plays a crucial role in determining fire flow. In order
for certain patches, which are locations in the environment, to burn, they
must have reached an ignition point, or minimal burn temperature. Each patch
owns different fuel types, amounts of fuel, spread rates, temperatures, and
other independent and dependent variables that define fire flow in the program.
The basis of this program, the Elliptical Fire Theory, has been verified through
empirical data collection. However, the limitations of this computer projection
are many. These limitations are related to the multitude of variables within
the fire flow process. Many of these variables could have been used, but much
more time and research are needed to do this. Thus far, this project has yielded
a foundation which can be built upon one step at a time.