熄灭森林阴燃火的细水雾喷头设计与仿真

森林大火后的残余地表余火及地下阴燃火是引起二次森林火灾的主要原因，为防止发生二次森林火灾，清理森林余火和阴燃火是必要的。细水雾作为哈龙灭火剂的最佳替代品，被广泛应用在消防领域。本文设计一种适合熄灭森林余火和阴燃火的撞击分流高压细水雾喷头，采用Fluent进行喷头流域的仿真，分析喷孔孔径、喷孔长度和喷孔喷雾锥角对喷出细水雾速度和喷雾保护半径的影响，并进行实验验证。Fluent仿真结果表明，细水雾速度受喷孔孔径和喷孔长度影响显著，并随喷孔孔径的加粗和喷孔长度减小而增大；喷雾保护半径受喷孔孔径和喷孔喷雾锥角影响显著，并随两者的增加而变大。采用Design-Expert分析出细水雾喷头最佳参数组合，将参数代入Fluent建立VOF-to-DPM（volume of fluid-to-discrete phase model，流体体积-离散相模型）细水雾喷头喷雾模型进行仿真，选用参数相近的细水雾喷头进行实验验证，实验测得喷雾保护半径与Fluent仿真结果误差为0.8％，证明优化和仿真结果合理。

Design and simulation of water mist nozzle for extinguishing smoldering forest fire

Residual surface fires and underground smoldering fires after forest fires are the main causes of secondary forest fires.To prevent secondary forest fires,it is necessary to clean up forest fires and smoldering fires.As the best substitute for halon fire extinguishing agent,water mist is widely used in the field of fire protection.In this paper,an impingement split-flow high-pressure water mist nozzle suitable for extinguishing forest fires and smoldering fires is designed.Fluent is used to simulate the nozzle flow area,and the nozzle hole diameter,nozzle length and nozzle spray cone angle are analyzed to spray the water.The influence of water mist speed and spray protection radius is testified by experiments.Fluent simulation results show that the velocity of water mist is significantly affected by the nozzle hole diameter,nozzle length and increases with the increase of the nozzle hole diameter and the decrease of the nozzle length;the spray protection radius is significantly affected by the nozzle hole diameter and the nozzle spray cone angle,and increases with the growth of both.Design-Expert is used to analyze the best parameter combination of water mist nozzles,and the parameters are substituted into Fluent to establish a VOF-to-DPM(volume of fluid-to-discrete phase model)water mist nozzle spray model for simulation.The water mist nozzles with similar parameters are selected for experimental verification,and the spray protection is measured by the experiment.The error between the spray protection radius and the Fluent simulation result is 0.8%,which proves that the optimization and simulation results are reasonable.