The performance of water-based fire suppression systems is governed by the dispersion of the water drops in the spray. Characterization of the spray is essential for predicting and evaluating the performance of these suppression systems. The dispersion of the spray is typically modeled using particle tracking methods. The accuracy of the spray predictions using this approach is quite sensitive to the initial spray specification. A physics based atomization model is proposed for specification of the initial spray. Inputs to the atomization model include injector geometry, injection pressure, ambient environment, and suppressant fluid properties. This modeling approach can be integrated with drop dispersion models and CFD models to characterize spray dispersion in quiescent environments or evaluate suppression performance in fire environments. In the current study, this atomization model is compared with measurements from an 'ideal' sprinkler to evaluate model performance and to support model development.

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