Numerical simulation to investigate the induced buoyant flow characteristics caused by intensive heat in complex curvilinear geometries

Abstract

AbstractThe buoyancy‐induced turbulent flows in complex geometries with internal heat source have important application in enclosure fire dynamics, for example, smoke movement in the situation of fire in tunnels. The majority of computational works studying the fire‐induced hot air movement in such cases use a Cartesian coordinate system. Hence, to simulate curved geometries, the Cartesian grid should be refined so that it comparatively matches the geometry. In the present work, a three‐dimensional numerical method using nonorthogonal curvilinear coordinate system was developed. Numerical simulations were performed to study the flow structures and the heat transfer characteristics of fire‐induced buoyant flow and the effects of using curvilinear coordinates on the result's accuracy and the computational cost. Numerical results were compared with the available experimental data and the results obtained by fire dynamics simulator (FDS) software. The results of the present method showed better agreement with the experimental results when compared with the FDS results.