Aliev E., Dudin V., Gavrilchenko A., Ivlev V. Modeling of the separation process for bulk material according to its physical and mechanical properties

UDC 004.94

 

E. Aliev

V. Dudin

A. Gavrilchenko

V. Ivlev

 

Purpose. Conduct numerical modeling of the process of bulk material separation under the action of air flow, vibrating sieve and solid vibrating surface in order to develop appropriate physical and mathematical models and to develop the proposed research methods.
Methods. The bulk material separation process was investigated in three stages of modeling in the STAR-CCM + software package by finite element method based on k-ɛ split-flow turbulence model, Van der Waals real-gas model, discrete element model and multiphase interaction model. The first step was to simulate the process of  bulk material moving under the action of airflow. Separation of bulk material on a small-sized cyclone-type aerodynamic separator was investigated. Also, for the implementation of the first stage of numerical modeling, a computational diagram of the process of the falling particles moving under the action of air flow was compiled. The second stage was aimed at modeling the process of moving the bulk material under the action of a vibrating sieve. The task of the third stage of modeling was to determine the particle distribution function of the bulk material by fractions under the action of a vibrating surface.
Results. The numerical simulation of the bulk material separation process on a cyclone-type small-scale aerodynamic separator resulted in the mass distribution of components by volume mass at the outputs of heavy and light components on the effective particle diameter and air velocity. As a result of numerical simulation of the mechanical and technological process of the bulk material moving under the action of air flow, the dependences of the distribution of each fraction of particles of the bulk material along the length of the region (fill factor, distribution coefficient) on the effective particle diameter, air flow rate and flow of bulk material were obtained. As a result of numerical simulation of the process of the bulk material moving under the action of the vibrating sieve, the dependence of the change of the total concentration and productivity on the bulk material flow, the angle of the sieve, the frequency of oscillations of the sieve and the amplitude of oscillations of the sieve are obtained. As a result of numerical simulation of the process of the bulk material moving under the action of the vibrating surface, the dependences of the change of the filling factor, the distribution coefficient and the productivity on the bulk material flow, the angles of inclination of the vibrating surface, the oscillation frequency, the amplitude of oscillations and the airflow velocity are obtained.
Scientific novelty. The general coefficients of  technological process quality in  separation of bulk material (coefficients of filling and distribution and total concentration of seeds) are offered.  The article obtains the mathematical models of the technological process of precision separation of the bulk material by its aerodynamic properties, geometric dimensions, bulk mass, which describe the change of the proposed quality coefficients depending on the regime parameters.
Practical importance. The obtained dependencies can be used in the designing of automated control systems of the constructive and mode parameters of bulk materials separators.

Keywords: bulk material, separation, modeling, aerodynamic properties, geometric dimensions, bulk weight.

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