Segregation of dry granular material in rotating drum: experimental study of the flowing zone thickness

Calibration and validation of DEM rolling and sliding friction coefficients in angle of repose and shear measurements

“…The polyamide spheres show high discrepancy between minimum and maximum inclination values. The size ratio d/D (where d is a particle diameter, and D is the drum diameter) is often used when describing granular flow in rotating drums [11]. It was reported that the angle of repose increase with an increase of the d/D ratio [12], which stays in contrary with our high velocity measurements.…”

Prediction of rolling bed motion in rotating cylinders

“…Experimental data of different sources are involved here: for fertilizer pellets from our experiments, polyethylene pellets (PE) from Boateng (1993), glass beads from Félix et al (2002), andJain et al (2002). For the calculation it is assumed that the glass beads used by the cited researchers have the same dynamic angle of repose as that given in Table 1.…”

“…The scaled thickness of the cascading layer was found to increase with increasing Froude number and with an increase in size ratio d/D (particle diameter to cylinder diameter). Félix et al (2002) measured the maximum thickness of the cascading layer in the range of rolling and cascading motion. The following conclusions were made: for large d/D ratios, the thickness of the cascading layer is determined by the geometry of the cylinder and it is nearly unaffected by the rotation speed, whereas for small d/D ratios, the thickness increases continuously with the rotation speed.…”

The maximum thickness of upper shear layers of granular materials in rotating cylinders

“…Data on the maximum thickness of the upper shear layer has been published by Henein et al (1983a), Woodle and Munro (1993), Boateng and Barr (1997), Van Puyvelde et al (2000) and Felix et al (2002). These data sets include shear layers formed from polyethylene, rice, oilshale, limestone, sand, plastic saddles, plastic shells, plastic tubes, and glass beads, and are summarized in Table 3.…”

“…For example, Van Puyvelde et al (2000) reports the percentage of the area of bed contained in the shear layer, whereas the other authors report the thickness of the shear layers. Felix et al (2002) use spherical particles, whereas Woodle and Munro (1993) use particles with aspect ratios of up to 5. Consequently, there are author-and particle-dependent factors contained in the data sets referred to above.…”