Mathematical Modeling of the Process of Movement of Grain Material on the Surface of a Sieve of a Vibrating Pneumatic Pulse Separator

Abstract

The results of a theoretical study of the movement of grain material on the surface of a unfailing sieve of a vibrating pulse separator are presented. The paper presents the power and kinematic model, geometric characteristics of the surface of the sieve of a vibrating pneumatic pulse separator in static, and kinematic processing parameters. Calculations based on the proposed model allow determining the forces of movement, velocity, and acceleration of seeds in the grain medium under the combined action of vibrations and pneumatic pulse flow. The following conclusions were drawn as a result of the research and analysis of the generated forces according to the developed mathematical model: the greatest influence on the process of moving grain material, both in the horizontal and vertical directions, is exerted by the force of impulse (pulsation) of the air flow, the pressure force above the overlying layers of grain material (for seeds in the middle part and on the surface of the sieve without a dip), friction forces, seed weight, and the Archimedean force; in order to intensify the process of fractionation of the grain medium, increase the productivity of the vibrating pneumatic pulse separator, it is necessary to increase the force of the pulsating air flow, the inertia of the oscillatory motion, friction and lateral pressure on the seeds in the grain medium. To solve this problem, it is necessary to optimize the amplitudes and frequencies of oscillations of the unfailing sieve of the vibrating pneumatic pulse separator. The analysis of the mathematical model showed the feasibility of using a vibrating unfailing sieve surface with the simultaneous interaction of the injecting pulsating air flow under the sieve to separate grain material by seed density. It has been established that in order to intensify the separation of grain material into fractions, while increasing the productivity of the technical means, it is necessary to increase the force of the pulsating air flow, friction forces, and lateral pressure. The dynamic model of the movement of grain material displacement and recombination is scientifically substantiated and technological recommendations for the separation of grain material into fractions by seed density using the proposed technical means of a vibrating pneumatic pulse separator with the use of a patented method of its separation are developed.