Abstract: In order to study the sprinkler distrbution characteristics performance of special application sprinkler system in large-span space public buildings, based on the previous development of extra large orifice closed sprinkler（flow coefficient K≥ 400）, another two types of special application sprinkler（K-161 and K-363）were selected, and the tests of sprinkler distribution of three kinds of sprinkler were carried out under the condition of installation height of 22 m and spray density of 32 L/(min?m2) and 36 L/(min?m2) respectively. The results show under the influence of sprinkler water deflector and pressure fluctuation, the deviation of spray intensity decreases with the increase of flow coefficient, and the uniformity of spray intensity is greatly affected by the working pressure. The smaller the working pressure is, the better the uniformity is.

Key words: fire protection, special application sprinkler, spray density, deviation, homogeneity variance