PDI Probes:
Droplet size and velocity measurements

Demeter​

The Demeter PDI Probe has been specifically designed for agricultural applications that require turnkey operation in the field under difficult operating conditions. It measures  the size and one component of velocity of individual spray droplets as they enter the measurement probe volume. Various spray statistics such as mean diameter, median diameter, and size-velocity correlation are computed and displayed in real-time. The probe can be used for characterizing spray nozzles, studying spray deposition, and measuring spray drift. The probe can also be used for wind tunnel testing and can be mounted in an aircraft for aerial spraying applications.

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The probe includes an optical transmitter and optical receiver which are packaged together in an aerodynamic, water-tight enclosure. Demeter electronics (ASA and computer) are mounted in a vibration isolation rack system which also serves as the shipping container. The system is aligned and calibrated in the factory. Routine alignment and calibration are not required. The operating measurement size range can be manually changed by the user. The high powered DPSS laser built into the probe provides stability, compactness, ruggedness, and high reliability; it eliminates the need for inefficient and unreliable fiber optics and bulky Ar-ion lasers.