| Summary: | 碩士 === 長庚大學 === 化工與材料工程學系 === 98 === This work used Eulerian continuum model to simulate particle motion and segregation in a rotating drum rotating at 10 rpm、20 rpm、30 rpm rotational speeds.
The results from the 2D simulations show that (1)when particles are smaller, the velocities of the particles down the bed surface are faster and the surface of the bed is easier to form the concave kidney shape;(2)as the rotational velocity of the rotating drum is increased, the velocity of the granular flow in the drum is also increased.
When we used the Gidaspow model to calculate the collisional kinetic viscosity of the solids phase, the simulated dynamic angle of repose did not agree with the measured dynamic angle of repose. When the collisional kinetic viscosity of the solid phase was calculated using the 2D approximation method on dynamic angle of repose in 3D simulation, the simulated dynamic angle of repose also did not show good agreement with the experimental measurements. When the collisional kinetic viscosity of the solid phase was calculated using the 3D approximation method on dynamic angle of repose, the segregation phenomenon was well simulated. The small particles were wrapped by the large particles after about one revolution. After a few revolutions, the segregation core was dimilished, the small particles concentrated to the center of rotating drum, resulting the formation of the segregation band. The 3D segregation structure was also in good gualitative agreement with the experimental result.
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