CFD simulation of multiple solutions of smoke flow in a simple building

Abstract

As for a simple single-zone building on fire under an opposing wind with one small top opening on one side and one small bottom opening on the other side, computational fluid dynamics (CFD) using Fluent software is employed to simulate smoke mass flow rate and smoke flow direction. A two-way simulation approach is used in the simulation to consider the effect of different initial conditions. The simulation results are compared with previous macroscopic analysis in Gong and Li (2008), and they fit well with macroscopic analysis. A hysteresis phenomenon is found during the process of simulation, streamlines and isotherm contours for both the buoyancy-dominated flow and the wind-dominated flow under the same wind speed and fire power are then given to validate the existence of multiple solutions of smoke flow. The effect of multiple solutions of smoke flow on the smoke control is finally discussed in realistic situations. The existence of solution multiplicity of smoke flow in a simple building shows that a further study of more complex and realistic situations is necessary.