Title: Transiently Jammed Fronts in Shear Thickening Suspensions under Impact

Author (Talk): Shomeek Mukhopadhyay, Yale University

Abstract:

We study the impact response of shear thickening suspension of cornstarch and water under normal impact at constant velocity in three dimensional experiments. Using high speed imaging of the top and bottom surfaces, particle tracking and normal force measurements we observe the existence of two distinct propagating fronts which scales with the impactor velocity with two different exponents. Forces and particle movement can be observed when the fronts interact with the boundary. We also observe an apparent shear thickening transition, where above a critical velocity the normal stress increases by orders of magnitude. In the high stress regime, we measure localized force distribution on the bottom surface, similar in nature to a granular pile.