Abstract The process of foam formation in sprinklers (nozzles) for automatic extinguishing systems at present is poorly studied. There are no analytical models for predicting this process due to the presence of many complex physicochemical, mechanical and other phenomena. Previously, the authors studied the influence of the geometric parameters of the sprinkler (the frame arms and deflector) on the foam expansion rate K. The sprinkler with optimal geometry (the OFS sprinkler) capable to generate foam with expansion rate K of 13.6 was developed. In this work, the OFS sprinkler was tested under conditions close to a real fire. The comparison of the extinguishing efficiency of the OFS sprinkler with three deflector type sprinklers widely used in automatic foam extinguishing systems is presented. Fire extinguishing efficiency of the tested sprinklers was compared by using the extinguishing efficiency indicator Et, which takes into account the extinguishing time of the model fire site and specific discharge of the extinguishing agent. It was found that the fire extinguishing efficiency of the OFS sprinkler is more than 2.5 times better compared with the other tested sprinklers.

中文翻译：

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为更高膨胀率而优化的偏转型洒水喷头与其他泡沫和泡沫水洒水喷头的现场测试和灭火效率比较

摘要 目前，对自动灭火系统的喷头（喷嘴）泡沫形成过程的研究很少。由于存在许多复杂的物理化学、机械和其他现象，因此没有用于预测该过程的分析模型。之前，作者研究了喷头（框架臂和偏转器）的几何参数对泡沫膨胀率 K 的影响。 开发出能够产生膨胀率 K 为 13.6 的泡沫的具有最佳几何形状的喷头（OFS 喷头） . 在这项工作中，OFS 洒水喷头在接近真实火灾的条件下进行了测试。介绍了 OFS 喷头与广泛用于自动泡沫灭火系统的三偏转型喷头的灭火效率的比较。通过考虑模型火灾现场的灭火时间和灭火剂比排放量的灭火效率指标Et，比较了被测洒水喷头的灭火效率。结果发现，与其他测试喷头相比，OFS 喷头的灭火效率提高了 2.5 倍以上。