直升机动力舱灭火剂扩散仿真分析

Simulation of Extinguish Agent Diffusion in Helicopter Engine Compartment

建立了某型直升机的动力舱模型;通过ICEM-CFD软件对直升机动力舱几何模型进行网格划分;采用FLUENT软件模拟不同通风量下直升机动力舱的初始通风流场;基于DPM模型模拟动力舱通风状态下灭火剂从喷嘴释放及雾化扩散的过程;分析了三种通风流量下的动力舱灭火剂浓度变化情况。结果表明:动力舱内灭火剂浓度均满足航标HB7879-2008的灭火剂体积浓度大于6%且持续时间大于0.5 s的要求,达到了该型直升机动力舱灭火系统的设计要求。

In this paper,the engine compartment model of a certain helicopter was established.ICEM-CFD software was used to grid the geometric model of the helicopter engine compartment.FLUNT software was used to simulate the initial airflow field of the helicopter engine compartment under different ventilation rates.Based on the DPM model,the release of extinguishing agent from nozzle and atomization diffusion process in engine compartment under ventilation were simulated,and the change of extinguishing agent concentration in engine compartment under three ventilation flows was analyzed.The results showed,the concentration of extinguishing agent in the engine compartment met the navigation mark requirements(HB 7879-2008)of the volume concentration of fire extinguishing agent greater than 6%and the duration of fire extinguishing agent greater than 0.5 s,which met the design requirement of extinguishing system in engine compartment of a certain type of helicopter.