Smoke Movement in Corridors: Adding the Horizontal Momentum Equation to a Zone Model.
Smoke Movement in Corridors: Adding the Horizontal
Momentum Equation to a Zone Model.
(467 K)
Jones, W. W.; Matsushita, T.; Baum, H. R.
U.S./Japan Government Cooperative Program on Natural
Resources (UJNR). Fire Research and Safety. 12th Joint
Panel Meeting. October 27-November 2, 1992, Tsukuba,
Japan, Building Research Inst., Ibaraki, Japan Fire
Research Inst., Tokyo, Japan, 42-54 pp, 1992.
Keywords:
fire safety; fire research; corridors; smoke movement;
equations; zone models; heat transfer; experiments;
computer models
Abstract:
The most common type of models utilized to study
building fires are referred to as zone models. The
motivation for using such models in preference to a
complete implementation of the Navier Stokes equation is
the great difficulty in obtaining solutions of the
latter in realistic fire scenarios. One uses only a few
elements, or zones, per compartment, and thus can apply
the technique to many compartments. A more complete
description of zone models is given elsewhere. This
type of model works well in many cases. However, for
long rooms or tall shafts, the basic tenet of the finite
element concept as applied to fires is violated. The
idea is that within an element, or zone, the gases are
uniformly mixed, and there is no bulk velocity of the
gas. To simulate smoke movement in large buildings, it
is important to predict movement of the smoke front
(nose) in the corridor or shaft. Although the ideas
which we will discuss are also applicable to tall
shafts, there will be differences in both the equations,
and their implementation. This paper concentrates on
the flow along a horizontal corridor.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899