Fire-Driven Flows in Enclosures.
Fire-Driven Flows in Enclosures.
(717 K)
McGrattan, K. B.; Rehm, R. G.; Baum, H. R.
Journal of Computational Physics, Vol. 110, No. 2,
285-291, February 1994.
Keywords:
enclosures; equations; viscosity; thermal conductivity;
vorticity; backdraft; gravity current
Abstract:
A two-dimensional Boussinesq model describing
heat-driven, buoyant convection in a polygonal enclosure
is presented. The hydrodynamic model is based on the
time-dependent Navier-Stokes equations with constant
viscosity and thermal conductivity; no turbulence model
or other empirical parameters are introduced. The
polygonal domain is mapped via a numerical
Schwarz-Christoffel transformation onto a rectangle,
where the equations of motion are written in terms of
the vorticity and stream function. An alternating
direction implicit (ADI) difference scheme, second-order
in space and first-order in time, is used to integrate
the evolution equations, and a standard elliptic solver
is used to solve the Poisson equation for the stream
function. Computational results which are of interest to
the fire research community are presented.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899