Experimental study of gas-powder fire extinguishing agent application via a slotted nozzle for pool fire suppression

Subject. The article addresses methods for enhancing the effectiveness of extinguishing fires caused by spills of flammable liquids. The study aims to determine the optimal parameters for supplying a gas-powder fire-extinguishing agent (GPFEA) through a slotted spray nozzle.

Objectives. The objectives of the research include analysing the influence of the nozzle position, GPFEA discharge rate, and fire area size on the extinguishing efficiency.

Methods. Experimental studies were conducted using simulated fire sources of various configurations. A slotted spray nozzle, positioned at a fixed distance from the edge of the model fire source, was employed to supply the GPFEA. The diaphragm coefficient of the nozzle was determined as the ratio of the lateral slot area to the cross-sectional area of the GPFEA supply line.

Results. The experiments demonstrated that effective extinguishing of flammable liquid spills is achieved when the GPFEA discharge intensity exceeds 1.4 kg/(m²·s). The fan-shaped jet produced by the slotted nozzle must completely cover the fire area to ensure full suppression.

Practical significance. The obtained results can be applied in the development of more efficient fire suppression systems for industrial facilities where flammable liquid spills may occur. The findings are of practical relevance for improving the safety of oil and gas industry facilities.

Conclusions. The study confirmed the effectiveness of using a slotted spray nozzle for extinguishing flammable liquid spills. To further enhance extinguishing performance, it is essential to consider the nozzle orientation, mass flow rate, and discharge intensity of the GPFEA. Future research should focus on studying the formation mechanism of the zone with a fire-extinguishing concentration of the GPFEA above the spill surface.

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