INTERPRETING MEAN DROP DIAMETERS USING DISTRIBUTION MOMENTS

The relationship of mean drop diameters to distribution moments is examined. Parent distributions for each mean diameter are identified. The conventional interpretation of each drop diameter is expanded by examining the underlying relationship of each mean diameter to its parent distribution. Each mean diameter is derived based on distribution moments. The resultant derivations show that the physical meaning of each drop diameter is, in many cases, different from the conventional definition. For example, D20 is often referred to as the surface area mean diameter. However, in a statistical sense, D20 is not a mean diameter but a measure of the spread of the number-weighted diameter distribution. D32, the Sauter mean diameter, is the surface area mean diameter based on distribution moments.