An Experimental and Numerical Exploration of Acceleration-Induced Cavitation in Soft Gel

Soft hydrogels are widely used to simulate biological tissue. When subjected to an impact, the gels’ typical mechanical response is associated with the cavitation of bubbles. Because of the complexity of the phenomenon and the difficulties related to experimental measurements, cavitation in soft gels is still a subject of investigation. This contribution uses experimental data from drop-tower tests to study the behavior of impact-induced cavitation in agarose gels of different concentrations and, thus, stiffness. The critical acceleration that induces bubbles to cavitate is investigated. Utilizing an adapted Rayleigh-Plesset equation, the corresponding pressure-dependent bubble motion is calculated. Finite element computations validate the measurements, derive the relevant pressure fields, and track the pressure-dependent bubble volume. The proposed strategy allows an efficient modeling and offers new insight into understanding cavitation in soft tissue simulant materials under high-energy impact loading.