Fire Safety Science Digital Archive

The 'superdrop' method, which characterizes a sprinkler as a statistical representation of a number of real drops, has been revisited. The intensive experimental data of a Wormald 'A' cu/p sprinkler in the pendant position has been used for its development, optimization and evaluation. An alternative 'meandrop' method, which characterizes the sprinkler spray by a simplified representation of the drop-diameter histogram associated with each emission sector of the spray, has been proposed to rectify the limitations associated with the need to use statistical distributions and weighting adjustment methods in the superdrop method. The superdrop and meandrop methods for characterizing the sprinkler have been implemented in the two-phase multi-cell zone sprinkler model SPLASH and the two-phase CFD JASMINESPARTA sprinkler model. The sensitivity of the predicted heat transfer on the spray to the number of superdrops or meandrops released per emission sector, and the effect of the sprinkler on the buoyant hot smoke layer due to a fire in an enclosure have been examined.