Suppression of Cavity Formation by Dense Suspension Droplets Impacting Immiscible Liquid Pools

Cavity suppression during impact on liquid pools is desirable in many applications such as food processing, medical storage, and bioprinting. It has been found that the impact of a solid sphere can suppress cavity formation under certain conditions, while it is challenging for the impact of a liquid droplet. Dense suspensions can switch between liquid‐like and solid‐like behaviors, serving as an ideal candidate for cavity suppression. In this talk, we will report the cavity formation behavior when dense cornstarch droplets (volume fraction Φ = 47.5 %) impact immiscible pools of different viscosities at varying impact velocities. We found that only a narrow window of velocity and pool viscosity suppresses cavity formation. Scaling analysis shows that jamming transitions in the suspension droplets and the dynamics of the contact line synergistically controls the cavity formation. Our findings deepen the understanding of suspension droplet impacts on liquid surfaces and the role of jamming transitions in these dynamics, which offers practical guidance to control cavity formation or suppression.