AEM Mechanics Research SeminarTuesday 14-Oct-2025, 12:20pm Central
Mr. Ankit KumarDepartment of Aerospace Engineering and Mechanics, University of Minnesota
Title: Kinetics of impact induced cavitation in water: a Combined Theoretical and Experimental StudyAbstract: When liquids are exposed to rapid dynamic loading from explosions, impacts, or certai
medical procedures, they can experience tensile stresses that drive
them into metastable states. These stresses can trigger phase
transformation from liquid to vapor, a phenomenon known as cavitation.
While extensively studied in the quasistatic regime, the kinetics of
cavitation under dynamic loading remains a fundamental challenge. In
particular, classic models of fluids with phase change (i.e., models
like the van der Waals gas) exhibit non-uniqueness of what are expected
to be well-posed problems. Unlike ordinary shock waves, this issue is
not resolved by including viscosity.
In this study, we develop a theoretical framework to solve the
two-phase Riemann problem associated with the dynamics of phase
interfaces during impact-induced cavitation. This formulation models the
dynamic evolution of liquid-vapor interfaces under transient tensile
stresses generated by impact loading. To experimentally validate this
framework, we designed a modified liquid Hopkinson bar setup to generate
controlled stress waves in a confined water column. Through the
interaction of rarefaction waves, a disk-like region of large negative
pressure is produced, enabling observation of cavitation phenomena in a
quasi one-dimensional framework. High-speed diagnostics are employed to
probe the nucleation and growth of this disk, providing insight into the
kinetics of impact-induced phase transitions.
This combined theoretical and experimental approach establishes
a foundation for quantifying the kinetics of cavitation under impact.
Beyond fundamental interest, these findings have potential implications
in diverse applications, from blast-induced traumatic brain injury to
industrial processes where rapid pressure changes in confined fluids may
induce phase transformation.For more information, visit the AEM Mechanics Research Seminar website: