Running on fluid: The impact-induced hardening on dense suspensions

We simulate the impact-induced hardening in dense suspensions with the lattice Boltzmann method that incorporates the contact between suspended particles and the free surface of the suspension. First, we analyze the rebound motion of a free-falling spherical impactor on top of the suspensions, how the frictional interactions between suspended particles affect the rebound, and how to characterize the topological structure of the dynamically jammed region beneath the impactor [1]. Then, we discuss the connection between the rebound motion, the impact speed, and the maximum force acting on the impactor, by proposing a phenomenology that can recover the viscoelastic response of the impactor during the impact [2].