REC «Mekhanobr-Tekhnika» (Russia):

Vaysberg L. А., Corresponding Member of RAS, Doctor of Engineering Sciences, Professor, Scientific Supervisor, gornyi@mtspb.com

Ivanov K. S., Ph. D. in Engineering Sciences, Researcher, ivanoff.k.s@gmail.com

In screening process modeling, applying universal approaches as the discrete elements method, consideration of particle shape factor, accomplished, as a rule, by means of «glued» spheres approximation, is associated with an increase by the factor of many times in computing requirements, which, even without that, are significantly high. The problem of consideration of particle shape is also not sufficiently dealt with in conventional modeling methods. The article presents an analysis of bulk material particle shape factor effect upon its sieve classification. For that purpose, the full-scale experiments’ results are compared with numerical simulations data, obtained through author's software effective computing medium. With that, particle shape is considered both in conventional spherical approximation, and in ellipsoidal approximation. Approximation parameters with respect to specific experimental material samples are established by means of image analysis methods. As a result, it is shown, that particle shape factor effect upon sieve classification process may be significant. Computational accuracy, with regard to ellipsoidal approximation, perceptibly exceeds that of regarding conventional spherical approximation. An improved formula is proposed for a single particle of ellipsoidal shape passing through sieve rectangular mesh, and may be used in calculations that employ any computational model.

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