DROPLET SIZE MEASUREMENT
BETE Spray Laboratory
The size of the droplets a nozzle produces can affect process performance. For example, a process may require a mist with tiny droplets that can evaporate quickly, or it might need a spray with larger droplets that fall against an upward-moving airflow. BETE Engineers use two instruments to measure the size of droplets in a spray. Each offers different types of analysis depending on the data required.
BETE Model 700 Imaging Particle Analyzer
The BETE Model 700 Imaging Particle Analyzer consists of a video camera and microscope lens, and a strobe light opposite the camera illuminates the droplets from behind. A strobe flash timed with a video frame and image processing software analyzes the droplet images, converting them to a physical size based on a calibration done using a reticle or a ball bearing. The imaging system can measure large non-round droplets and droplet diameters from 25μm -20,000 μm.
TSI Phase-Doppler Particle Analyzer (PDPA)
The Phase-Doppler Particle Analyzer uses the interference of the light in two laser beams to measure both droplet size and droplet velocity in two planes. It is beneficial for measuring droplet sizes in the 1μm-5,000 μm range.
The Phase-Doppler Particle Analyzer uses the interference of the light in two laser beams to measure both droplet size and droplet velocity in two planes. It is beneficial for measuring droplet sizes in the 1μm-5,000 μm range.
TSI Phase-Doppler Particle Analyzer(PDPA)
Considerations
Each of the instruments has advantages and limitations, as shown in the table below. The PDPA is non-intrusive, can measure tiny droplets, and is also able to measure velocity. The Model 700 imaging instrument can capture images of the large non-round droplets common in industrial sprays, but it is slightly intrusive. Both instruments have difficulty performing with dense sprays.
Contact Us
Are you ready to see how BETE can help? Let us know what you need by contacting Daniel deLesdernier. We’ll work with you to plan a project that meets your needs and budget.
While, as a matter of course, we maintain confidentiality, we are always willing to negotiate special confidentiality agreements if necessary.
