Optimisation of a circularly vibrating screen based on DEM simulation and Taguchi orthogonal experimental design

Laboratory-scale validation of a DEM model of screening processes with circular vibration

A numerical study of the motion particulates follow along a circularly vibrating screen deck was done using the three dimensional Discrete Element Method (DEM). The motion of the particles was analyzed. The effects of vibration amplitude, throwing index, and screen deck inclination angle on the screening process are discussed. The results show that the average velocity of the particles increases along the longitudinal direction of the deck. The screening efficiency is highest when the vibration amplitude, throwing index, and screen deck inclination angle are 3–3.5 mm, 2.7 and 15°, respectively. This work is helpful for developing a deep understanding of particle motion and for optimizing screen separator designs.

Simulation of the screening process on a circularly vibrating screen using 3D-DEM

https://isiarticles.com/bundles/Article/pre/pdf/41636.pdf

Cuckoo search algorithm based on frog leaping local search and chaos theory

A review on the advanced design techniques and methods of vibrating screen for coal preparation

The vibration property of a rectangular-hollow-sectional beam with an external crack were theoretically and experimentally studied in this paper. The external part-through crack and through-thickness crack were considered. Linear elastic fracture mechanics were employed to establish the theoretical formula for computing the equivalent torsion spring stiffness of the two external cracks. Then, the experimental method of obtaining the equivalent torsion spring stiffness was developed. It is seen that the test data match fairly well with the analytical data. On this basis, the transfer matrix method was introduced to obtain the frequency equations of these cracked beams under three classic boundary conditions, and followed by the numerical method for calculating natural frequencies. Experimental tests on clamped–free beams were used to verify the accuracy. It should be noted that a part-through crack may lead to a more distinct natural frequency reduction than the through-thickness crack.

Vibration analysis of a rectangular-hollow-sectional beam with an external crack:

This paper briefly introduced the structure of concentration-driven flip-flow screen. Created a model of flip-flow screen motion simulation in Pro/ENGINEER, get the kinematic curve of midpoint of sieve plate, and compared the results with theoretical analysis, verify the feasibility of the design. Checked the motion interference of flip-flow screen, found a lot of problems during the movement of flip-flow screen, made some changes on two-dimensional drawings, reduce the cost of manufacturing.

Motion simulation and interference checking of concentration-driven flip-flow screen

The primary goal of this research is dynamics modeling and analysis of spatial parallel manipulator with flexible links. A new model of spatial finite element beam model is proposed. The kinematic constraint conditions of the moving platform and the branches of the spatial flexible parallel manipulator are derived. The dynamic model of the moving platform is developed based on the Newton-Euler principle. Then, using the kinematic constraint equations and dynamic model of the moving platform, the overall system dynamic equations of the parallel manipulator are obtained through assembling the dynamic equations of elements. Finally, the numerical simulation of a 3-RRS parallel manipulator was presented and compared with the results of SAMCEF software simulation. The results showed that the effectiveness and correctness of the dynamic models proposed in this paper.

Kinematic constraint conditions and dynamic equations of spatial flexible parallel manipulator

The dynamics of 3-DOF spatial parallel manipulators with flexible links were performed. Firstly, a model of spatial flexible beam element was proposed, and the dynamic equations of elements and branches of the parallel manipulator were derived. Secondly, using the kinematic and dynamic constraint equations of the parallel manipulator, the overall system dynamic equations of the parallel manipulator were obtained by assembling the dynamic equations of branches. Thirdly, the dynamic responses of the 3-RRS parallel mechanism with flexible links were analyzed through numerical simulation. This paper can provide necessary information for the dynamic performance analysis, dynamics optimization design and control of the 3-RRS flexible parallel mechanisms.

Dynamics of 3-DOF spatial parallel manipulator with flexible links

Aiming at the problems of penetration and missing detection between particles with high speed in virtual system, a dynamic detection algorithm is presented which efficiency is advanced by the combination of multilevel detection and detection space division method in this paper. The algorithm has been applied in virtual sieving experiment system of discrete materiel and the results meet a good agreement with industrial experiment. It shows that dynamic collision detection algorithm can avoid the problems of penetration and missing detection between particles with high moving velocity and improve the precision of virtual sieving test. The algorithm is simple and with high efficiency which is suitable for simulation of complex virtual scene with large number of dynamic particles.

Liu Chusheng

Papers

Vibration analysis of a rectangular-hollow-sectional beam with an external crack:

Motion simulation and interference checking of concentration-driven flip-flow screen

Kinematic constraint conditions and dynamic equations of spatial flexible parallel manipulator

Dynamics of 3-DOF spatial parallel manipulator with flexible links

Dynamic collision detection algorithm and application