Experimental study on merged flame characteristics from multifire sources with wood cribs

Experimental study on flame merging behaviors from two pool fires along the longitudinal centerline of model tunnel with natural ventilation

“…Weng et al . [5] studied the multiple wood crib fires in open space. They measured HRR and MLR and calculated combustion efficiencies of both single flame ( χ) and merging flames ( χ m ).…”

“…Once the fires are located sufficiently close to each other, the air entrainment around the flames could be restricted and the resulting pressure drop between fires might lead to flame merging which will cause the increase of flame height compared to a single fire [2,3] . The flame merging will make the fire more destructive, leading to difficulties in firefighting and may even lead to fire whirls [2][3][4][5] . Therefore, it is worthwhile to study the interacting fires.…”

“…However, most of them [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] were conducted in open space to investigate the effects of fuel type, fire shape, size, number, spacing and array pattern on the mass loss rate (MLR), flame height, flame merging, heat feedback, fire whirl, etc.. For example, Weng et al [2] , Kamikawa et al [3] and Fukuda et al [4] studied the effects of fire spacing and heat release rate (HRR) http …”

“…They concluded that the spacing has a weaker impact on the flame merging compared to the fire number and HRR. Weng et al [5] studied multiple wood crib fires and found that increasing the spacing and the burner number enhanced the combustion efficiency. Huffman et al [6] found that the MLR of multiple pool fires with luminous flames increases and then decreases with decreasing the spacing.…”

Effects of pool size and spacing on burning rate and flame height of two square heptane pool fires

“…When the fires are located sufficiently close, the restriction of air entrainment will lead to a pressure drop between fires, resulting in flames tilt to each other and even merge together [7]. The interaction of multiple flames might cause increases of burning rate and flame height when compared to a single flame [8]. The enhanced heat feedback to the fuel and flame outward radiation due to interaction raise the possibility of fire ignition and flame spread.…”