Determination of oscillation parameters of the elastic screen of a vibrating sieve using explicit and implicit dynamics methods for a rubber element

Abstract

Screening is one of the key operations in the processing of bulk materials. During operation, the design of screening surfaces must ensure high efficiency depend-ing on classification conditions and maintain consistent sieve aperture sizes for as long as possible to minimize oversize or undersize fractions of the classified material. The Department of Industrial Engineering at UDUNT has developed a new design of an elastic screening surface with high operational performance. The objective of the study is to determine the dynamic parameters of motion of the ele-ments of a card-type elastic screen in a vibrating sieve. A finite element model of the card-type elastic screen element was developed for dy-namic analysis. The rubber was modeled as a nonlinear hyperelastic material with the Neo-Hookean model. A dynamic calculation was performed using both explicit and implicit dynamics meth-ods, and the kinematic characteristics of selected points (displacement, velocity, and accel-eration) were obtained. The maximum deformations ranged between 0.12% and 30%, which justifies the use of the Neo-Hookean model. Velocity and displacement results showed minor differences between the methods. How-ever, acceleration values revealed more significant discrepancies. Explicit dynamics intro-duced high-frequency oscillations with greater amplitudes, leading to noise in the results. This is due to the inherent characteristics of the explicit integration method, which used a time step of approximately ~10-7sec. The study also established the dependence of oscillation amplitude on the vibrator fre-quency and on the elastic modulus of the screen element.