Pisarakokoja

Pisarakokoja is a term used in fields such as aerosol science, meteorology, agriculture and medicine to denote the range of sizes of liquid droplets produced by atomization, spraying or natural processes. The concept encompasses droplets that range from submicrometre to several millimetres in diameter, with size distributions often summarized by a mean diameter and a spread.

Classification and typical values: In aerosol applications, droplets are commonly categorized as submicron (<1 µm), fine (1–10 µm) and coarse (10–100 µm), while spray nozzles can generate droplets from about 50 µm to several hundred µm. In cloud physics, most atmospheric droplets are on the order of 10–50 µm, whereas raindrops are larger, up to millimetres in diameter.

Measurement methods: Droplet sizes are measured with optical particle counters, laser diffraction analyzers, and cascade impactors. Each method has different ranges of accuracy and is chosen based on the expected size distribution and the medium being studied.

Applications and implications: Droplet size influences evaporation rate, transport by air, and deposition on surfaces or within the respiratory tract. In agriculture, droplet size affects drift and spray coverage; in medicine, it determines where aerosols deposit in the lungs; in climate science, it affects cloud reflectivity and precipitation formation.

See also: aerosol science, spray technology, cloud microphysics, deposition.