Analyzing and Exploiting Numerical Characteristics of Zone Fire Models.
Analyzing and Exploiting Numerical Characteristics of
Zone Fire Models.
(943 K)
Forney, G. P.; Moss, W. F.
NISTIR 4763; 44 p. March 1992.
Fire Science and Technology, Vol. 14, No. 1/2, 49-60,
1994.
Available from:
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Keywords:
zone models; fire models; computer models; numerical
analysis
Abstract:
In order to design robust and stable zone fire modeling
algorithms, the numerical properties of computer
arithmetic and modeling differential equations must be
understood. This report examines some of these
properties and provides tools for their analysis. Many
sets of different equations for zone fire modeling can
be derived using the conservation of mass and energy. A
comparison between various possible formulations is made
in terms of numerical properties. One property that
many formulations possess is the presence of multiple
time scales. Pressures equilibrate much faster than
other quantities such as density and temperature.
Numerically, this property is known as stiffness.
Stiffness, in the context of fire modeling, and
numerical methods for handling it are discussed.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899