李权威^*， 冯明辉

（  南京理工大学化工学院；  ）

摘要： 本文对超细水雾熄灭杯式燃烧器中火焰的最低灭火浓度进行了数值模拟和实验研究。 利用修改的全混流反应其模型对超细水雾熄灭乙醇和正庚烷的最低灭火浓度进行了测量，其结果分别为19.50%和14.87%（质量分数）。在自建的超细水雾发生装置上测量得到超细水雾熄灭乙醇和正庚烷的最低灭火浓度分别为13.89%和12.59%，预测误差分别为40.39%和18.11%。本文对模型的假设进行了分析，探究了造成模型误差的原因。对于不同的燃料，灭火剂浓度对燃料蒸发速率的影响、超细水雾对火焰辐射的衰减等因素与假设的偏差使得预测值产生了偏差。
关键词： 安全技术及工程；超细水雾；杯式燃烧器；最低灭火浓度；全混流模型

Li Quanwei^*， Feng Minghui

（  School of Chemical Engineering,Nanjing University of Science and Technology,Nanjing,210094；  ）

Abstract： The interaction of ethanol/ n-heptane flame and ultrafine water mist was investigated numerically and experimentally to have some knowledge about UFM's extinguishing features and testify the accuracy of a modified PSR model. The predicted critical mass fractions of UFM in the oxidizer streamwere19.50% and 14.87% respectively. Experiments were performed on a self-designed apparatus to determine the MECs for the ethanol and n-heptane flame. The measured critical mass fractions of UFM extinguishingethanol and n-heptane flame were13.89% and12.59%, 40.39% and 18.11% higher than the predicted values respectively. An analysis was performed on the assumptions of the model. It was found that the influences of droplet evaporation process and radiation attenuation could not be neglected for flame extinction.
Keywords： Safety technique and engineering; Ultrafine water mist; Cup burner; Minimum extinguishing concentration; Perfect Stirred reactor