Granular rheology: measuring boundary forces with laser-cut leaf springs

In granular physics experiments, it is a persistent challenge to obtain the boundary stress measurements necessary to provide full a rheological characterization of the dynamics. Here, we describe a new technique by which the outer boundary of a 2D Couette cell both confines the granular material an...

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Bibliographic Details
Main Authors: Tang Zhu, Brzinski Theodore A., Daniels Karen E.
Format: Article
Language:English
Published: EDP Sciences 2017-01-01
Series:EPJ Web of Conferences
Online Access:https://doi.org/10.1051/epjconf/201714003035
Description
Summary:In granular physics experiments, it is a persistent challenge to obtain the boundary stress measurements necessary to provide full a rheological characterization of the dynamics. Here, we describe a new technique by which the outer boundary of a 2D Couette cell both confines the granular material and provides spatially- and temporally- resolved stress measurements. This key advance is enabled by desktop laser-cutting technology, which allows us to design and cut linearly-deformable walls with a specified spring constant. By tracking the position of each segment of the wall, we measure both the normal and tangential stress throughout the experiment. This permits us to calculate the amount of shear stress provided by basal friction, and thereby determine accurate values of μ(I).
ISSN:2100-014X