Scalings of axisymmetric granular column collapse

TLDR: In this paper, a 3D laser scanner was used to measure the final pile radius and the column radius was found to be dependent on the aspect ratio of the initial geometry as previously thought, but also the initial column radius and hence the ratio of column radius to particle diameter.

Abstract: Experimental investigations into the collapse of granular columns are presented with dimensional results of the final deposit obtained using a 3D laser scanner. The high accuracy measurement method has found that the final pile radius is not only dependent on the aspect ratio of the initial geometry as previously thought, but also the initial column radius and hence the ratio of column radius to particle diameter. This was also observed to be true for the angle at the base of the deposit. Theoretical considerations coupled with obtained data have allowed the angle at summit for aspect ratios less than approximately 3 to be described entirely in terms of material parameters and aspect ratio—something desired for all length scalings but seemingly unobtainable due to the dynamic nature of the collapse. With the method being non intrusive, measurement of the summital radius was also made possible. The final height showed a dependence predominantly with aspect ratio in agreement with previous authors.