EXPERIMENTAL-EVIDENCE OF A GENERAL DESCRIPTION FOR RAINDROP SIZE DISTRIBUTION PROPERTIES

A body of previous theoretical and experimental studies suggests that there is a general formulation for raindrop size distribution properti es able to describe them in a wide variety of rain conditions. The for mulation basically relates the evolution of the drop populations to a rain bulk variable, such as the rain rate. This paper proposes a simpl e methodology to carry out testing in order to seek experimental evide nce of such a description. Four data sets from diverse devices, locati ons, and climates are used in an event-by-event analysis. The results show good general agreement between data and theory in regard to of th e defined criteria: linear increase in the exponents of bulk variables relationships and self-consistency of the fitting procedure, leading to an experimental confirmation of the general description and its imp licit hypothesis. The question of the number of parameters and the sha pe of the function needed to identify drop size distribution are discu ssed at different levels of the study. Dimensional considerations abou t the general expression are given in the appendix.