Abstract:Aiming to lack of accurate discrete element simulation parameters in the simulation analysis of roasted green tea refining equipment, taking roasted green tea as the research object, the discrete element simulation parameters of roasted green tea were calibrated. The contact parameters between roasted green tea and materials were measured by using the inclined plane method and the free fall method to determine the range of values for static friction coefficient, rolling friction coefficient, and collision recovery coefficient. The actual stacking angle of roasted green tea was obtained through bench tests of the cylinder lifting method. A discrete element model of roasted green tea was established, and the formation process of stacking angle was simulated. Using the actual stacking angle of roasted green tea as the response value, the Plackett-Burman experiment was used to screen out the parameters that had a significant impact on the stacking angle of roasted green tea. The steepest climb test was used to approximate the optimal response range, and finally the optimal combination of significant influencing parameters was obtained through Box-Behnken. The results showed that when the shear modulus was 2.930MPa, the coefficient of static friction between tea particles was 0.771, the coefficient of rolling friction between tea particles was 0.133, and the coefficient of collision recovery between tea particles was 0.354, the simulated stacking angle of roasted green tea was 30.12°, and the error with the actual stacking angle was 1.59%. The optimized calibration parameters can be used to simulate the external contact characteristics of roasted green tea.
