Investigations regarding the influence of particle shape on the numerical simulation of air pluviation using the dem method

                                
==Abstract==

Air pluviation or sand raining is a method in geotechnics to create homogenous sand samples [1]. To investigate the behavior of the sand particles during pluviation, DEM (discrete element method) can be used due to its ability to realistically model particle interactions [2] with other sand particles or the pluviation equipment. These interactions are in turn influenced by the material as well as interaction properties and particle scaling. However, particle shape also influences the behavior such that realistically considering real-world particles’ shapes may improve modelling of the pluviation process.
To investigate the influence of particle shape on the simulation of air pluviation, three different numerical representations for sand particles will be used: (I) homogenous sand with spherical particles, (II) homogenous sand with uniform non-spherical particle shape, representing the average particle shape, and (III) heterogenous sand with varying particle shapes. The non-spherical particles are created using bonded spheres. For investigation of the pluviation process four partial processes were identified which are most likely to be influenced by particle shape: (I) the outflow out of the sieve, which regulates deposition intensity, (II) interactions with the diffusor sieves, which distribute the sand homogeneously over the sample surface, (III) free falling and the resulting particle interactions as well as (IV) the resulting sample density. For these processes, the impact of particle shape will be determined, including resulting particle velocities, angular velocities as well as the reached sample density. The results will, were applicable, be compared to results of physical experiments for further evaluation and validation.