Generally speaking, the packing fraction is one of the most important parameters, when handling powder. Various methods for handling powder and measuring their properties are standardized and included in the Japanese Industrial Standard (JIS). However, there is no standard on how to treat or handle particles of irregular shapes or rough surfaces. Within this frame there is a need for calculating the packing fraction of particles of irregular shapes.
In this study, three different methods are employed and the obtained results are compared. Three different methods are (1) controlled volume method, (2) balance method, and (3) apparent volume method, in the context of the discrete element method (DEM), and the results are compared for pointing out the advantages and disadvantages of each method. As a result, (1) the controlled volume method enables the accurate calculation of the packing fraction although different values for the bed volume can be obtained due to the random packing; (2) balance method is simple and easy but sacrifices the accuracy in the calculated packing fraction; (3) apparent volume method, on the other hand, is the most suitable method for calculating the packing fraction. It is simple and accurate, since it excludes from the calculation the area or the gap between particles.
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