Namyi (Nami) Ha

BioE Ph.D. Proposal Presentation

Date and Time: Friday, April 3rd, 2026, at 3:00 PM (EST)

Location: MRDC Conference Room 4211

https://gatech.zoom.us/j/99885496059?pwd=D1jd6ojMSZhX6m0xgLaSelnhG1p4aS.1

Advisor: Saad Bhamla, Ph.D. (Chemical and Biomolecular Engineering, Georgia Institute of Technology)

Committee:

Daniel Goldman, Ph.D. (Physics, Georgia Institute of Technology)

David Hu, Ph.D. (Mechanical Engineering, Georgia Institute of Technology)

Sunghwan (Sunny) Jung, Ph.D. (Biological and Environmental Engineering, Cornell University)

Itamar Kolvin, Ph.D. (Physics, Georgia Institute of Technology)

Ultrafast Fluid Ejection in Biological Systems: The Spotted Lanternfly as a Dual-Mechanism Honeydew Removal Machine

This thesis proposal delves into the physical mechanisms of phloem sap-feeding insects to understand how they efficiently eject fluid droplets under strong capillary constraints. By combining high-speed imaging, micro-CT imaging, kinematic analyses, and fluid property measurements, Aim 1 will seek to uncover how biological morphology and rapid actuation enable droplet detachment in the spotted lanternfly (Lycorma delicatula), revealing a developmental mechanism switch from a capillary ratchet in nymphs to an elastic catapult in adults. Aim 2 will develop reduced-order mathematical models to capture the underlying physics of these distinct ejection strategies and integrates these models into a scaling framework using dimensionless parameters across organisms. Finally, Aim 3 will map the actuator and droplet response phase spaces to establish the theoretical kinematic limits of these ultrafast rotational movements and analyze divergent post-launch spinning droplet dynamics. Together, this work will fill critical gaps in our understanding of fluid-ejecting biological systems and provide general design principles for novel bioinspired fluid transport and antifouling devices.