Abstract: To establish the key performance parameters and evaluate the fire extinguishing ability of compressed air foam fire extinguishing system in super high?rise building, the compressed air foam generating devices with adjustable mixed liquid flow rate and gas-liquid ratio are used to test the discharge characteristics of typical 19 mm foam nozzle under different conditions. The quantitative relationships between discharge characteristics of foam nozzle and input parameters such as mixed linearly with the gas-liquid ratio were analyzed. The foam range has a positive correlation with the gas-liquid ratio, and the foam multiple increases first and then decreases with the increase of gas-liquid ratio. Under certain gas-liquid ratio, the foam nozzle pressure increases linearly with the flow rate of mixed liquid, the foam range is positively correlated with the flow rate of mixed liquid, and the variation of the foam multiple with the flow rate of mixed liquid is closely related to the actual size of the gas-liquid ratio.

Key words: compressed air foam, discharge characteristics, super high?rise buildings, foam nozzle, gas liquid ratio, mixed liquid flow rate, foam range