Physical and contact material parameters.

To strengthen the screening efficiency of traditional vibrating screens, a new type of vibrating screen, namely the composite vibrating screen, has been proposed based on the Lissajous vibration synthesis theory. The working principles of composite vibrating screens have been explained. Numerical simulations of the sieving processes for such composite vibrating screens were carried out using the discrete element method. Compared with traditional linear vibrating screens, the force, stratification mechanisms, and throwing principles of the material on the screen’s surface were studied, and the vibrating screens’ material transportation and screening efficiency were analyzed. The results showed that with the existence of xyz three directions sub-vibrations of the composite vibrating screens, the material particle group is more diversified by the forces, the particle system is loose, the stratification effects are adequate, and the material is evenly distributed on the screen surfaces. Under the same vibration parameters, the composite vibrating screens’ screening efficiencies and material transportation capacities were better than those of linear vibrating screens. This work provides a necessary reference for the development and application of new composite vibrating screens.