Experiment And Simulation Study On The Extinguishing Properties Of K80 Closed Fire Sprinklers

Fire sprinklers is one of the most important components in the automatic sprinkler system. It sets detecting, automatic starting and sprinkling in one. Fire sprinkler extinguishing properties include the spray property and the response characteristic in the fire environment and the sprinkler distance under different conditions. The study of the extinguishing performance plays an important role in improving the ability of the extinguishing sprinkler system. The K80 fire sprinkler is one of the most widely used among so many types of the nozzle. It can be used in mild, moderate, severe danger level and some other places.There is a relevant provision in the Automatic sprinkler system design specifications about the type of the sprinkler. Its max headroom is 8.0m. The specification for clearance within 8.0m sprinkler arrangement are based on the same criteria without considering the impact of the height and the pressure of the sprinkler. It will bring a huge waste of the resources of water during present days that the sprinkler system is extensive used. At the same time, it will increase the cost of the building fire engineering.The article analysis the K80 sprinkler head from its sprinklers feature, sensing feature and its layout spacing. It analysis the characteristics of K80 sprinkler at different height and working pressure. the stability of sprinkler, the water box and water rate as well as the distribution of the intensity in the radial direction of the sprinkler nozzle by sprinkler nozzle test. By sprinklers spraying experiment, the spray property of K80 closed sprinkler at different heights and working pressure, and the catchment rate of water box, and the distribution of intensity in the radial direction of the sprinkler nozzle were tested and analyzed. The results showed that water density distribution in the radial direction is uneven, the lower the water pressure, the higher the altitude the more uniform intensity distribution of water. The fact showed that the impact of height to the minimum fire power was much more apparent than that of the response time index, the relationship between the sprinkler response time and the two parameters, the height of the sprinkler and the horizontal distance from the sprinkler to the center of the fire, are approximately linear correlation.Using fire simulation software, FDS, K80 closed fire sprinkler response characteristics were simulated to study the variation of the lowest fire power causing sprinklers response and sprinkler response time under different headroom. Based on the research of sprinklers Water spray characteristics and response characteristics, the paper presented a calculation method of the nozzle arrangement pitch. This method had considered the influence of the mounting height and sprinkler working pressure on the Sprinkler distance. The paper presents the concept of effective protection sprinkler radius, obtained the effective protection radius and arranged sprinkler spacing at different heights and working pressure in both meeting the specifications for Extinguishing sprinklers watering strength requirements, but also considering the height and pressure effects on water density conditions. Finally, the use of the FDS fire simulation software is simulated the fire-fighting capability of the sprinkler spacing requirements under two different arrangements. This paper analyzes the results of the analysis showed that the spacing arrangement can be achieved with the same regulatory requirements disposing pitch extinguishing effect.