Energy dissipation of binary powder mixtures subject to vibration

This paper presents an investigation of energy dissipation of vibrating bin ary powder mixtures packed naturally at low acceleration levels. A model ba sed upon both viscoelastic and two-phase theories has been developed to pre dict the dissipation energy of binary mixtures packed naturally. Two experi mental systems including open-top and top-cap systems were used to measure the properties of the mixture beds subject to vibration. The open-top syste m provides the dissipation energy rate of a powder bed packed naturally. On the other hand, the top-cap system produces the elastic and damping proper ties of a powder bed with a top-cap mass as a loading weight. The model dev eloped uses the elastic and damping properties of the powder bed deduced fr om the top-cap data to predict the properties of beds packed naturally. Com parison between the model and experimental data obtained by the open-top sy stem has been made, and good agreement between the model prediction and the experimental data was obtained. This has implications for the damping mech anisms and dynamics of binary powder mixtures packed naturally under vibrat ion.