Study On The Relationship Between Discharge Conditions And Class B Flame-Extinguishing Effect Of C₆-Fluoroketone

C6-Fluoroketone has been known as a new Halon replacement extinguishing agent because of its low extinguishing concentration, low GWP, safety and no remains. As HFC-227 or other fluorine-containing fire extinguishing agent has been confined for its high GWP, C6-Fluoroketone has been more and more widely used in developped countries. Although it has not been permitted to use in China so far, it is definite that it will be agreed in use in near future. Therefore, it is necessary that the interaction between C6-Fluoroketone and flame should be studied as soon as possible.By constructing the discharge test bench of C6-Fluoroketone, this paper was to study the influence of filling conditions on the C6-Fluoroketone discharge, and evaluate the effect of filling and fire conditions on the C6-Fluoroketone extinguishing total flooding class B fire through extinguishing time and thermal decomposition gas products.As the result shows, with the increase in filling pressure, the discharge flow of C6-Fluoroketone increases. But when the filling pressure is above 2.5MPa, the discharge flow increases little. The total flooding class B fire can be extinguished rapidly by C6-Fluoroketone. Five thermal decomposition gas products are produced including hydrogen fluoride, hexafluoroproene and octafluoropropane in the fire extinguishing process. The bigger the filling pressure is, the shorter the extinguishing time and the less the hydrogen fluoride concentration will be. Compared with the nitrogen, the discharge flow of C6-Fluoroketone pressurized with carbon dioxide is slightly low, the extinguishing time is slightly long and the hydrogen fluoride concentration is slightly high. But the component of other thermal decomposition gas products is uncharged. The fire at different locations or with occlusion can all be extinguished successfully. The fire extinguishing time from short to long is in the center, in the corner and in the up-corner. The extinguishing time and the hydrogen fluoride concentration of the fire with occlusion are both similar to that without occlusion. As the increase in the heat release rate of n-heptane, the extinguishing time increases firstly, then decreases, and the hydrogen fluoride content increases.Only when the C6-Fluoroketone pressurized above 2.5MPa with nitrogen is discharged at the initial stage of fire, can the extinguishing time be shorter and the thermal decomposition gas products be lower.