Effect of gas species on fire extinguishment using two phase flow

In the fire extinguishment system by using two phase flow, when the gas phase uses different gas species, the fire fighting effects are different. Four gases were used as the gas phases like air, nitrogen, carbon dioxide and argon. The experiments were conducted in a room measured by 3.6 m 4.6 m 3.9 m and the fire sizes were 0.1 MW and 0.61 MW. The type K thermal-couple tree and Siemens oxygen analyzer Oxymat-61 were used to measure the fire temperature and oxygen concentration separately. The fire extinguishment characters using two phase flow water mist under different gas phase conditions were got. The mode of actions under different gas species on fire extinguishment was concluded and the reason that the difference takes place was analyzed. Compared with the single phase flow, it shows that the fire extinguishment efficiency by using two phase flow under low system pressure is equal to single phase flow under higher system pressure.