气固喷射器的干粉喷洒试验及喉嘴距尺寸  

Dry powder spraying experiment of gas-solid ejector and size of nozzle-throat distance

作　　者：向清江[1] 杜春伟 张贡赫 王希坤[1,2] XIANG Qingjiang;DU Chunwei;ZHANG Gonghe;WANG Xikun(National Research Center of Pumps,Jiangsu University,Zhenjiang,Jiangsu 212013,China;Maritime Research Centre,Nanyang Technological University,Singapore 639798,Singapore)

机构地区：[1]江苏大学国家水泵及系统工程技术研究中心,江苏镇江212013 [2]南洋理工大学海事研究中心,新加坡639798

出　　处：《排灌机械工程学报》2023年第5期493-498,共6页Journal of Drainage and Irrigation Machinery Engineering

基　　金：国家自然科学基金资助项目(52079057);应急管理部重点实验室开放课题项目(2019XFZB07,2019XFZB10)。

摘　　要：为了研究气固喷射器应用于干粉灭火系统时的特点,在搭建的小模型干粉喷洒试验台上开展了气固喷射器的干粉喷洒试验,以及采用离散相DPM模型开展了干粉颗粒轨迹追踪,主要分析了喷射器3种喉嘴距长度下对喷洒性能的影响.结果表明:在所试验的干粉平均粒径(d 50)为24.3μm和供给量为2 kg/min情况下,干粉的地面分布均匀性主要受供给气体工作压力的影响,工作压力越高,干粉分布越集中;喉嘴距的改变对地面中轴线上降尘量分布曲线影响明显,合适的喉嘴距下具有最高的分布曲线;数值模拟结果表明喷射器的吸入室内存在回流区域.喉嘴距的改变影响了干粉颗粒在吸入室内的停留时间.由追踪的粒径判断,喉嘴距较小时粉尘颗粒容易沉积在喷嘴下端.研究结果可为气固喷射器应用于灭火提供参考.In order to study the characteristics of gas-solid ejectors applied to dry powder fire extinguishing systems,the dry powder spraying experiment of gas-solid ejector was carried out on the small model dry powder spraying test bench and using the discrete phase DPM model to track dry power particle trajectory.The influence of three nozzle-throat distances of the ejector on the spraying performance was mainly analyzed.The results show that under the case of the average particle size d 50=24.3μm and the supply amount of 2 kg/min of the dry powder,the distribution uniformity of dry powder on the ground is mainly affected by the working pressure of the supply gas.With the increase of the gas working pressure,the distribution of dry powder is more concentrated.The change of the nozzle-throat distance has an obvious influence on the distribution characteristic curves of dry powder on the central axis,and the highest distribution curve is under the appropriate nozzle-throat distance.The numerical simulation results show that there are backflow zones in the inhalation chamber of the ejector.The residence time of dry powder particles in the inhalation chamber is affected by the nozzle-throat.According to the tracked particle size,dry powder tends to be deposited at the lower end of the nozzle with a short nozzle-throat distance.The conclusions provide a reference for the application of gas-solid ejectors in fire extinguishing.

关 键 词：气固喷射器 干粉 DPM模型 干粉分布均匀性 喉嘴距 

分 类 号：TP603[自动化与计算机技术—控制理论与控制工程] S277.99[自动化与计算机技术—控制科学与工程]