At the NWO Physics 2026 Conference in Veldhoven on 20–21 January, PhD candidate Alejandra Riveros Cortés presented her research as an oral contribution, sharing key results from her ongoing doctoral work with a broad physics audience.

Her presentation, titled “Drop lift-off from hydrophobic surface driven by inertial liquid micro-jet impact”, explores the interaction between high-speed liquid microjets and droplets resting on hydrophobic surfaces. This phenomenon is relevant to applications such as inkjet printing, surface engineering, and needle-free injection technologies.

The study combines experimental observations with numerical simulations to investigate how millimeter-sized water droplets respond to cavitation-driven microjet impact. Using dual ultra–high-speed imaging, the rapid deformation dynamics of the droplets were captured, while computational modeling provided detailed insight into velocity fields and energy transfer mechanisms.

Three distinct regimes were identified depending on jet velocity: deformation without lift-off, drop detachment, and drop fragmentation. The results show that lift-off occurs when the jet’s kinetic energy exceeds the surface energy of the droplet, while fragmentation requires rotational energy to surpass surface energy.

The oral presentation format allowed these findings to be effectively communicated, particularly through ultra–high-speed visualizations that highlight the transient dynamics of the process. The presentation stimulated engaging discussions and provided valuable feedback, contributing to the ongoing development of this research.

This contribution represents an important milestone in her PhD project and highlights the broader relevance of her work within the fluid dynamics and physics communities.