A two-dimensional Boussinesq model describing heat-driven, buoyant con
vection in a polygonal enclosure is presented. The hydrodynamic model
is based on the time-dependent Navier-Stokes equations with constant v
iscosity and thermal conductivity; no turbulence model or other empiri
cal parameters are introduced. The polygonal domain is mapped via a nu
merical 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, s
econd-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 wh
ich are of interest to the fire research community are presented.