Dense granular flows in rotating drums: A computational investigation of constitutive equations

Novel 3D measures of compressibility and isotropy (coaxiality collinearity) are proposed to test constitutive laws rotating drum flows using the DEM with μ(I) rheology is tested. The coaxiality measure produces a lower occurrence frequency than equivalent 2D simulation for nearly all angular separations, while collinearity shows minimal deviation. high degree facilitated by across gravity-driven, flowing layer, non-zero volumetric component velocity gradient tensor near bottom densely-packed rising en-masse layer. simulations facilitate which ultimately leads better regularisation equations. An empirically-derived friction law statistically fits when compared several other in literature; however, models fail capture behaviour at very low inertial numbers. failure suggests gross instability governing equations signature ill-posedness and/or shear banding.