Hypergravitational Rayleigh-Taylor instability in solids

Rayleigh-Taylor instability in solids results from the competition and dominance of the gravitational potential against the elastic counterpart. We reveal systematically the phenomenon of hypergravitational Rayleigh-Taylor instability in solids by exploiting a novel approach of centrifugal hypergravity. A hydrogel plate is placed in a centrifuge with its free surface transforming from a flat state to a patterned state as the centrifugal gravity increases and exceeds a certain threshold. The experiments show that the centrifugal hypergravity enhances the gravitational potential and thus may induce instabilities in thinner, lighter and stiffer hydrogel plates in contrast to the Earth gravity. There exists a dimensionless critical hypergravity for a wider range of geometric size, mass density, elastic modulus and gravitational acceleration, beyond which the post-buckling pattern is sensitive to the aspect ratio of the plate. We demonstrate that the theoretical results for the Earth gravity may be extended to hypergravitational scenario for plates with lateral boundary confinement. These findings may provide a better understanding of the stabilities in natural solids under hypergravity and may pave a new way of realizing specific fabrications in industries. (c) 2022 Elsevier Ltd. All rights reserved.