Portable Monodispersed Droplet Generator

Portable Monodisperse Droplet Generator (PMDG) is a compact battery-powered instrument that generates a jet of fixed-sized monodisperse droplets. 

The PMDG is ideal for field calibration of atmospheric measurement instrumentation such as in situ cloud probes and precipitation measurement instruments.

The principle of operation is based on disintegration of a cylindrical liquid jet caused by periodic disturbance applied to the jet, which makes it dynamically unstable under the action of surface tension — this effect is commonly referred to as Savart–Plateau–Rayleigh instability of a liquid column. The PMDG is ideal for field calibration of atmospheric measurement instrumentation such as in situ cloud probes and precipitation measurement instruments. The PMDG has recently been used to field calibrate the Mesa Photonics’ tethered-balloon-based cloud droplet measurement instrument (CDMS). The current version of PMDG produces a jet of monodisperse droplets 193 µm in diameter; the instrument weighs 25 lbs and has dimensions of 21″ × 13″ × 7.5″. The powering options include embedded rechargeable battery and AC/DC power supply. The power draw is 12 W; the battery operation time is about 5 h.