Flame height behavior from multi‐fire sources

The flame height behavior of merged or inclined flames from two rectangular fire sources in a parallel configuration and from three and four circular pools of 120 mm diameter in a symmetrical configuration were studied experimentally. A rectangular gas diffusion burner, 20 mm × 400 mm or 20 mm × 800 mm was used as line fire sources. Propane gas gave 9.5–57 kW per meter for each burner. Hexane was utilized for the flame merging test using circular pool fires. The height of the flame tip when merged or inclined due to interaction of the flames and|or convective flow was estimated from picture analysis of 300 successive frames of video-recorded data. The flame extension behavior was expressed in dimensionless form as L/Lm = (fs)2/5 for square pool fires and L/Lm = (f1)2/3 for rectangular fires. The correction factors of fs and f1 are fs = (nD2 + S2) / n(D2 + S2) and f1 = (2DW + S2) / 2(DW + S2), respectively. When a rectangular or a circular fire source approaches the wall, the same correlation on flame extension behavior was obtained and simulated successfully considering an imaginary fire source inside a wall.