Dynamics of crater formations in immersed granular materials

TL;DR

This study investigates how craters form and evolve on immersed granular beds under gas flow, revealing a logarithmic growth pattern and the influence of parameters like grain size and gas flow on crater dynamics.

Contribution

It provides a detailed analysis of crater formation in immersed granular materials, highlighting the logarithmic growth law and the effects of experimental parameters.

Findings

Crater size increases logarithmically with time.

Crater formation is independent of gas emission dynamics.

Grain size and gas flow significantly influence crater evolution.

Abstract

We report the formation of a crater at the free surface of an immersed granular bed,locally crossed by an ascending gas flow. In two dimensions, the crater consists of two piles which develop around the location of the gas emission. We observe that the typical size of the crater increases logarithmically with time, independently of the gas emission dynamics. We describe the related granular flows and give an account of the influence of the experimental parameters, especially of the grain size and of the gas flow.