消防专业论文-干粉灭火系统输送过程分析.docxVIP

PAGE III 干粉灭火系统输送过程分析 摘 要 干粉灭火系统是借助惰性气体的压力来驱动并携带干粉灭火剂，通过喷嘴固体粉末均匀喷洒实施灭火的灭火设施，干粉的输送属于气固两相流输送。在干粉颗粒的输送过程中，干粉颗粒的运动和分布状态，随着输送气体的速度、管径和管长的不同而改变。研究管道中干粉颗粒的运动和分布状态对于干粉灭火系统有着重要的意义。 本文针对气-固两相流的输送特点，本文利用Fluent软件，采用Euler模型和颗粒动力学方法对干粉颗粒在管道中的流动进行模拟，主要模拟了输送气体的速度、管径和管长改变情况下，干粉颗粒运动速度、体积分布率的变化。 模拟结果揭示了干粉输送过程中输送气体速度、干粉颗粒速度和颗粒体积分布率沿管长的变化规律以及管长、管径和驱动气体速度的改变对干粉颗粒分布和气固比的影响。以期为进一步优化干粉灭火系统输送参数提供理论依据，提高干粉输送效果。 关键词 干粉灭火系统； 气体输送； 气-固两相流； Fluent； 数值模拟 The analysis of transport process of the extinguishing fire system of dry powder Abstract Dry powder fire extinguishing system is the fire fighting facility which drive and carry dry powder fire extinguishing agent by the pressure of inert gas and spray solid powder uniformly through the nozzle. The delivery of dry powder delivery is gas-solid two-phase flow. In the process of the delivery of dry powder particles, the movement and distribution of the dry powder particles is changing with pressure of transported gas, diameter and bend of pipeline. Study on the movement and distribution of the dry powder particles in bend pipe has an important significance for the dry powder fire extinguishing system. Considering the characteristics of the transmission of gas-solid two-phase flow, we make simulation of the flow of dry powder particles in pipeline using the Euler model and the particle dynamics method by the Fluent software in this paper. The main simulation is how the velocity of dry powder particle and the volume distribution rate changes when pressure of transported gas, diameter and bend of pipeline is changing. The result of simulation shows not only the how the velocity of transported gas, the velocity of dry powder particle and the volume distribution rate of dry powder particle changes with the change of length of pipeline, but also how length of pipeline, diameter and the velocity of driving gas affect the distribution and gas-solid ratio of dry powder particle. This result have a further view to optimize the transmission parameter