| dc.description.abstract | The purpose of this study is to investigate the flow behavior of granular materials in cylindrical silos with different opening sizes and seven different inserts by experiment. The orifice size of silos were 10cm and 15cm respectively. These inserts include conical insert, disk insert, solid cylinder insert, sphere insert, BINSERT and hollow cylinder insert. Quasi-three-dimensional silo is proposed to mimc the flow behavior of granular materials in the three-dimensional silo. Both Particle Image Velocimetry (PIV) and Particle Tracking Velocimetry (PTV) methods were used to measure the velocity fields for the granular flow, and the corresponding results were compared and discussed. Furthermore, the effect of insert geometry on transport properties of the granular flow in the silo is analyzed. Key findings are highlighted below: (1) Generally, the velocity profiles for the granular flow obtained by the PIV and PTV measurement methods are quite consistent. However, there are some discrepancies at the exit and the side wall of silos, which needs to be further investigated; (2) For the silos with the conical insert, disk insert, solid cylinder insert and sphere insert, both measurement techniques show that the granular flow exhibits uniform vertical velocity profiles. However for the silo with the hollow cylinder insert, the granular vertical velocity inside the insert is much faster than that outside the insert, exhibiting an extremely uneven vertical velocity profile; (3) Compared with silos with no insert, 15cm-orifice silos with conical insert, disk insert, solid cylinder insert and sphere insert exhibit small and more evenly distributed granular temperature. Similarly, 10cm-orifice silos with conical insert and disk insert also show small and more evenly distributed granular temperature; (4) In the 15cm-orifice silos with no insert, conical insert, disk insert, solid cylinder insert, sphere insert and BINSERT, the distribution of fluctuation velocity is uniform and similar to the Maxwell distribution. By contrast, for the silo with hollow cylinder insert, the fluctuation velocity is widely distributed and exhibits an M-shaped distribution, indicating that the vertical velocity is not uniform; and (5) In the 10cm-orifice silo with conical insert, the fluctuation velocity shows the Maxwell distribution. However, for the silos with disk insert, solid cylinder insert, sphere insert and BINSERT, the distribution of fluctuation velocity is shifted to the right. For the silo with hollow cylinder insert, the fluctuation velocity is still distributed widely and unevenly. | en_US |