Experimental study of the development process and hazard scope of horizontally oriented liquefied gases jet fires

•The development of horizontally oriented liquefied gas jet fires is explored.•The effect of leakage hole area on the fire development process was quantified.•A prediction model has been established for the hazard scope of jet fires.•A fireball duration prediction model is proposed. This paper investigates the effects of injection pressure (Pin), leakage hole area (A) and shape on the development process and hazard scope of horizontally oriented liquefied gas jet fires. Liquid propane was used as the experimental medium, with leakage hole shaped as circles, squares, and triangles. The results show that flame development processes for leakage holes of equal area, regardless of shape, exhibit substantial similarities. As the leakage hole area increases, two distinct modes of fireball development at the flame tip emerge during flame progression. When A ≥ 3.14 mm2, the fireball at the flame tip undergoes a sequence of drop-rise-expand-detach-collapse-disappear. The flame size (length, height) in the presence of the fireball significantly surpass those after its disappearance. To construct an empirical model for the hazard scope of liquefied gas jet flames, the mass flow rate (mexp) was combined with the hydraulic diameter (de) to establish empirical formulas for the hazard scope of liquefied gas jet flames as well as fireball duration (td) applicable to circle and non-circle leakage holes.