飞机灭火管路三氟溴甲烷流动仿真

Simulation of Halon 1301 flow in aircraft fire extinguishing pipes

使用Amesim软件对某型飞机灭火系统管路建立了仿真模型,研究了灭火剂充装压力、灭火剂温度、管路粗糙度、灭火管路喷口直径、管路支管直径等参数的影响。发现在5.34 kg灭火剂充装量下,4,5,6 MPa充装压力下的灭火剂喷出质量曲线相近;灭火剂温度越低,喷射速度越慢,-50℃灭火剂的喷射时间约为-10℃的2.5倍;粗糙度对灭火剂喷射量也有明显影响,粗糙度越低,喷出量越快,但0.13 mm和0.20 mm粗糙度下的灭火剂喷出质量曲线相近;16,17,18 mm喷口直径对系统的整体灭火剂喷出质量影响很小,但喷口之间的流量分配会受到喷口直径变化的影响;当连接3个喷口的长支管和连接2个喷口的短支管直径组合为(16,14 mm)、(14,12 mm)时,2条支管的灭火剂喷出量之比接近1。

Simulation models were developed for an aircraft fire extinguishing system using Amesim software.The influence of the parameters such as the filling pressure,the temperature of the fire extinguishing agent,the roughness of the pipe,the diameter of the nozzle,and the diameter of the branch pipe of the pipeline were studied.It is found that under the filling mass of5.34 kg of fire-extinguishing agent,the spray mass curves of fire-extinguishing agent under the filling pressure of 4,5,and 6MPa are similar.The lower the temperature of the extinguishing agent,the slower the spray rate.The spray time of-50℃fire extinguishing agent is about 2.5 times that of-10℃.Roughness also has a significant effect on the amount of fire extinguishing agent sprayed.The lower the roughness,the faster the spray amount.The quality curve of fire extinguishing agent under the roughness of 0.13 mm and 0.20 mm is similar.The nozzle diameters of 16 mm,17 mm and 18 mm have little effect on the overall fire extinguishing agent spray quality of the system,but the flow distribution between the nozzles will be affected by the change of the nozzle diameter.When the diameter combination of the long branch pipe connecting 3 nozzles and the short branch pipe connecting 2 nozzles is(16,14 mm)and(20,12mm),the ratio of the amount of fire extinguishing agent sprayed from the two branch pipes is close to 1.