je rencontre com gratuit Piles of granular material built by gradually adding material at the top of the pile typically form a symmetrical cone shape. The slope angle of the side of the pile with respect to the horizontal is known as the angle of repose.
http://mt-creations.fr/wp-json/oembed/1.0/embed?url=http://mt-creations.fr/renouveler-lequipement-electromenager-afin-de-realiser-des-economies-denergie-2/ When modelling the flow of granular material with discrete element modelling there are a number of tests that may be used to calibrate the simulation against the real-world behaviour of the material. In free flowing situations it is normally sufficient to simply be able to reproduce the material’s angle of repose, which is primarily a function of particle shape and coefficient of friction. Typical tests for this are the slump test:
or the slowly rotating mill test:
However, when modelling the discharge of granular material from hoppers (silos, bins) or rail wagons where the material has been allowed to consolidate for a period of time, bonding of the material to itself or the walls must be considered. In this case it is essential for the DEM to be able reproduce shear cell (Jenike or box) tests – i.e. reproduce the material shear strength as a function of consolidation pressure. This is normally achieved through the use of contact bonding in the DEM model, but achieving a reasonable calibration requires is not trivial.