A molecular dynamics simulation of segregation behaviours of horizontally vibrated binary granular mixture

This paper performs the two-dimensional, soft-spheremolecular dynamics simulations to study the granular segregation ina binary granular mixture with the same size but different densityin the container with the sawtooth base under horizontal vibration.The segregation phase diagram is presented in theacceleration-frequency space. When the acceleration is high enoughto result in relative motions of the particles, the system can be invarious states (mixed state, vertical and horizontal segregationstate), which depend on both acceleration and frequency. Due to thesawtooth base there is stratified flow effect besides densityeffect. The density effect raises the light particles. Thestratified flow drives the particles in the upper levels to theright and the particles in the lower particles to the left, thosefact results in the appearance of the left segregation state. Theleft segregation state can be changed to the right segregation bychanging the shape of the sawtooth. As the vibration frequencyincreases, the stratified flow effect becomes weaker and weaker, soat high vibration frequencies the vertical segregation state appearsinstead of the left segregation state.