Representation of average drop sizes in sprays

Procedures are presented for processing drop-size measurements to obtain average drop sizes that represent overall spray characteristics. These procedures are not currently in general use, but they would represent an improvement over current practice. Clear distinctions are made between processing data for spatial- and temporal-type measurements (also referred to as concentration-sensitive and flux-sensitive, respectively). The conversion between spatial and temporal measurements is discussed. The application of these procedures is demonstrated by processing measurements of the same spray by two different types of instruments, a laser-diffraction drop sizer and a phase-Doppler particle analyzer.