细水雾灭火喷嘴的雾化特性测量

为了改善喷嘴的雾化效果和研究其喷雾过程，对直射式灭火喷嘴进行了加旋芯改进和实验测量.初
步探讨了旋芯式喷嘴的雾化机理，简述了三维相位多普勒粒子测速仪(PDPA)的系统参数、测量原理和测量
过程.施加不同的喷雾压力，分别测量了喷嘴无旋芯和有旋芯时的喷雾锥角并进行比较.在2.5 MPa喷雾压
力时，测量了旋芯式喷嘴喷射的雾滴分别在喷雾中心和边缘处的索太尔雾滴直径(SMD)、轴向速度、径向
速度和切向速度并进行对比.结果表明，与没加旋芯的喷嘴相比，加旋芯的喷嘴有更大的喷雾锥角和更好
的雾化效果，其雾化过程符合稳定性理论规律；在喷雾中心和边缘处，喷雾参数有显著的区别.

Measurement of atomization characteristics on water mist fire suppression nozzle

For better atomization effect and helping understanding of the atomization process, a direct-jet nozzle for fire suppression was improved by introducing a swirl chamber, and the spray characteristics were investigated. The primitive atomization mechanism was discussed, and the system parameters, measurement principles and measurement process of 3D phase doppler particle anemometer (PDPA) were presented. Different pressures were applied to the nozzle, and the spray cone angles with and without the swirl chamber were measured. With the spray pressure was 2. 5 MPa, the sauter mean diameter (SMD), the axial, radial and tangential velocities were measured, and the experimental data on the location of spray axial center were compared with those on the location of spray external edge. The results show that the nozzle with swirl chamber has larger spray cone angle and better atomization effect compared with the nozzle without one, and that the nozzle's atomization process agrees with the stability theory. The spray characteristics have remarkable influence on the spray axial center and on the spray external edge.