Research On The Actual Delivered Density（ADD） TestApparatus

Automatic sprinkler system is one of the most important and widely-used fireprotection systems. Sprinkler as the terminal component of the automatic sprinklersystem, whether it can sprinkle enough water through fire plume, of which theperformance concerns the fire extinction and fire control effect of the system. Theactual delivered density, the ADD is an essential index to test the penetrationcapability of water drops and evaluate the performance of sprinklers. Therefore theestablishment of the ADD test equipments has great significance to the test onperformance of sprinklers and development of the sprinkler products.This paper mainly introduces the performance and technical requirements ofESFR (Early suppression fast response) sprinklers that have been applied in someoccupancies with high fire hazard such as warehouses. It also analyses the currentsituation of ADD test apparatus at home and abroad. The ADD test apparatus hasbeen designed and set up according to performance requirement of ESFR sprinklers.In this paper, the design principles of the test apparatus, ignition and air supplysystem, data acquisition and processing system, collecting system and water systemhave been specified in detail. Calibration test of ADD apparatus and ADD test onESFR sprinklers have been done by the equipment to research. It determines thetechnical parameters of ADD test and analyzes the main influence factors on ADDtest.The tests indicate that this equipment is reasonably designed, stable and reliable,easy to operate and the measurement and control system is highly automatic, bywhich remote-control auto ignition and the data automatic collection can beachieved.On the whole, the equipment with high precision is able to simulate thetemperature and wind of the full fire test. The ADD test on ESFR sprinklers alsoindicates that the ADD value is mainly concerned with such factors as the pressureof sprinkles, the distance of clear ceiling, and the heat release rate and so on. TheADD value decreases as the heat release rate increases.The automatic measurement on sprinkling density, computer control analysis,automatic data-out test method are adopted by this equipment, which has changed the present manual measurement methods of foreign countries, eliminatingman-made influence, thus greatly increasing work efficiency and measurementaccuracy. The measurement method of the equipment exceeds the technical levels ofinternational test set of the same kind and the measuring and testing techniquereaches international advanced level.