Abstract Three-phase foam, namely surfactant-particle stabilized foam is a promising material in pool fire extinguishment. However, its effectiveness has not been validated. In this study, a research-scale three-phase jet foam generator, which allowed adjustments of foam slurry composition, nozzle type, air flow rate and screen aperture, was developed. In order to optimize the foaming condition, a three-factor three-level Box–Behnken design (BBD) was adopted. Fly ash (FA) particles were used as the solid phase to generate three-phase foams. As a result, the FA supported foam exhibited better stability over conventional fire-fighting foam, especially when the particle concentration exceeded a threshold value. In addition, the BBD results presented a good agreement between experimental data and fitted models. The optimal foaming condition was determined by numerical optimization. Small-scale fire extinguishing experiments were carried out and three-phase foam manifested better burnback performance compared to conventional fire-fighting foam. The design in this work can be used to study the firefighting efficiency of different three-phase foams and serve as a prototype to develop better generators for both lab research and practical application.

中文翻译：

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基于Box-Behnken设计的研究型三相射流泡沫发生器设计及发泡条件优化

摘要 三相泡沫，即表面活性剂-颗粒稳定泡沫是一种很有前途的水池灭火材料。但是，其有效性尚未得到验证。在这项研究中，开发了一种研究规模的三相喷射泡沫发生器，可以调整泡沫浆液成分、喷嘴类型、空气流速和筛网孔径。为了优化发泡条件，采用了三因素三水平 Box-Behnken 设计（BBD）。飞灰 (FA) 颗粒用作固相以生成三相泡沫。因此，FA 支撑的泡沫比传统的消防泡沫表现出更好的稳定性，尤其是当颗粒浓度超过阈值时。此外，BBD 结果在实验数据和拟合模型之间呈现出良好的一致性。通过数值优化确定最佳发泡条件。进行了小规模灭火实验，与传统灭火泡沫相比，三相泡沫表现出更好的回火性能。这项工作中的设计可用于研究不同三相泡沫的灭火效率，并作为原型为实验室研究和实际应用开发更好的发生器。