It is well known that water mist had been regarded as an efficient and environmentally friendly fire suppression technology due to its merits of pollution-free, high efficiency and low cost. However, the conventional one is limited to relatively short spray range and radial coverage, while the turbojet-engine-based one has several shortcomings known as high costs, excessive power consumption and high noise, etc. So in order to meet the urgent need for efficient fire suppression of a large-scale fires and the safe long-distance decontamination of the leaked hazardous chemicals, the research group of Prof. Xishi Wang and Xiaolong Zhu from SKLFS, proposed and developed an advanced water mist generation method based on axial flow induction for range extension and rotation-precession jet coupling for spray enhancement, which enables the long-range and wide-area dispersion of water mist under standard power conditions.

With collaboration of Beijing Nari Yihe Co., Ltd., they developed a turbofan water mist system with spray distance upto 30 m, and an environmentally compliant film-forming foam agent tailored for transformer fire scenarios especially act as water mist additives for reducing mist droplet size, suffocating oil fires and efficiently washing away smoke particles. Full-scale verification tests were conducted via suppression of an 800 kV converter transformer fire, and the results well confirmed its high effectiveness. The theoretical/semi-empirical models on spray distance prediction and influencing factors analysis have also been developed.

Chart of Long-Range Foam-Water Mist Firefighting Technology. (a) Axial Flow Induced long-range Spray Principle Schematic and Theoretical Analysis. (b) Optimization of Environmentally Friendly Film-Forming Foam. (c) Principle of Droplet Decontamination of Flue Gas. (d) Real Scene of Firefighting at 800 kV Substation.