Research on Vaporization and Sudden Cooling Performance of Heptafluoropropane in Prefabricated Fire-Extinguishing Devices Based on Numerical Method

With the safety and reliability of the electrical equipment used in information systems becoming more important, prefabricated fire-extinguishing devices using heptafluoropropane as the extinguishing agent have broad application prospects. However, few studies have focused on the vaporization performance of heptafluoropropane in the context of fire suppression and the safe distance for electrical equipment. This study proposes a numerical simulation model to analyze the vaporization and cooling performance of sprayed heptafluoropropane. First, experimental measurements with no fire source are performed to verify the numerical model. Through numerical and experimental methods, the temperature, concentration, and velocity distribution of the sprayed heptafluoropropane are analyzed to improve its vaporization performance and determine the safe distance. Finally, heptafluoropropane spraying with a fire source is simulated, allowing for the discussion of its cooling effect and fire-extinguishing performance. The results illustrate that the mass ratio of liquid and gas phases in the sprayed heptafluoropropane are 20.2% and 79.8%, respectively. Heptafluoropropane spraying reduced the average temperature in the protective room, with the final value reaching 270 K. The mass fraction of the heptafluoropropane maintained a value of 0.1 at a distance of 0.8 m in front of the nozzle axis. The main findings of this research indicate the temperature variation and fluid flow performance associated with heptafluoropropane spraying, as well as providing a reference value for a safe distance from the nozzle.