Numerical Simulation on Fire Phenomena During Simultaneous Fires in Two Rooms Connected by Side Opening

Numerical simulations were conducted to analyze fire phenomena in two rooms connected by a side opening, each containing a single fire source. The two rooms (Room-A and Room-B) were connected via Opening-A, with Room-B also connected to the outside via Opening-B. Fire sources with heat release rates of 2.605 kW (Case1) and 5.21 kW (Case2) were placed at the centers of both rooms. The results were compared with those of previous numerical simulations of a single 5.21 kW fire source placed in either Room-A (Case3) or Room-B (Case4). Flow velocities through Opening-A were lower in Case1 and Case2 than in Case3, with Case2 exhibiting higher velocity than Case1. The flow velocity through Opening-B was highest in Case2. When a fire source was in Room-A, mass flow rates through Opening-A were lower in Case1 and Case2 than in Case3, while Case2 showed the highest mass flow rate through Opening-B. When a fire source was in Room-B, Case2 exhibited the highest mass flow rates through both openings, and Case4 the lowest. The highest hot gas layer (HGL) temperature rise and thickness were observed in Case2, while the lowest HGL temperature rise was observed in Case1. The thinnest HGL was observed in Case3 and Case4 when the fire source was in Room-A and Room-B, respectively.