Controllable and uniform microdroplet generation is essential for many applications in biology and chemistry including cell handling and aerosol drug delivery. This report described experimental characterization of a novel ultrasonic droplet generator that allows for dynamic control over ejection behavior. That is, the operation frequency and drive voltage can be modified in real-time to achieve a desired device operation. An improved system configuration provides high-resolution stroboscopic imaging of the microscopic ejection behavior. Fabrication of microarrays with a central active nozzle isolates a single ejection process for unobstructed imaging. In this independent study, I assisted in characterization of both full-array and single-orifice droplet generator configurations. With this, we have observed that increasing the drive voltage leads to greater ejection instability and ejection mode transitioning. The latter relationship has lead us to revisit our existing predictive regime map.
Mechanical Engineering and Material Sciences Independent Study
Date of Submission
Krippner, Kyle, "Macroscopic and Microscopic Characterization of Droplet Breakup Regimes Using a Novel Ultrasonic Droplet Generator" (2021). Mechanical Engineering and Materials Science Independent Study. 168.