Abstract: The discharging flow rate and time are the core parameters for evaluating the fire suppression efficiency of new high-boiling-point gas fire suppression systems, such as those based on FK-5-1-12. This paper focuses on the complex gas-liquid two-phase flow characteristics during the discharging process of high-boiling-point fire suppressants, systematically comparing the applicability of turbine flowmeter, thermal mass flowmeter, and Coriolis mass flowmeter. Through actual measurement analysis, it is determined that the turbine flowmeter is the optimal measurement scheme. At the same time, combined with theoretical analysis and experimental verification, the physical determination criteria for the discharge stop point are established, achieving the objective definition of the start and stop times of the discharge. This measurement method has both high accuracy and universality, and can be applied to different system structures and operating conditions, with significant economic benefits and engineering guidance value. The research results could provide key technical support for the performance evaluation, design optimization, and standard formulation of new gas fire suppression systems.

Key words: high-boiling-point gas fire extinguishing system, discharging process, gas-liquid two-phase flow, discharging time, judgment criterion