Arching phenomena of particulate materials in a shaker

The motions of particulate materials in a vertical shaker are complicated. According to the levels of the amplitude of vibration acceleration, the particle motion phenomena may have the following convective types: heaping, coherent, expansion, wave and arching. This paper studied the arching phenomena of granular materials in a vertical shaker. The arching motions were investigated by high speed photography and image processing technology. The velocity fields of the granular materials during vibration were calculated from the recorded images. The ensemble averaged velocities in horizontal and vertical directions were close to 0. The velocity fluctuations were also measured. The ensemble averaged granular temperature was increased with the amplitude of the vibration acceleration, however, the variation of granular temperature in horizontal direction with acceleration is not significant due to the existing sidewalls.