关键词: 羌活籽粒, 珍珠岩, EDEM, 参数标定, 堆积角, 条播

Abstract: In order to determine the physical parameters required for discrete element simulation of seed metering device of Notopterygium, the physical parameters of seeds and pearlite of Notopterygium were measured and calibrated. The static friction coefficient was measured using the inclined plane method, the collision recovery coefficient was measured using the free drop method, the accumulation angle was measured using the cylinder lifting method, the accumulation angle was compared by EDEM simulation to determine the rolling friction coefficient, and the accuracy of the measured parameters was determined by comparing the results of simulation test and field test. The grain density of Notopterygium seeds was 160 kg/m3, and the pearlite density was 150 kg/m3. The Poissons ratio of Notopterygium seeds was 0.32, and that of pearlite was 0.2. The shear modulus of Notopterygium seeds was 30 MPa, and that of pearlite was 38.5 MPa, the static friction coefficient between Notopterygium grain and ABS plastic plate was 062, the static friction coefficient between pearlite and ABS plastic plate was 0.78, the static friction coefficient between Notopterygium grain and ABS plastic plate was 0.51, the static friction coefficient between pearlite was 0.91, and the static friction coefficient between Notopterygium grain and pearlite was 0.72. The collision recovery coefficient between Notopterygium grain and ABS plastic plate was 0.39, the collision recovery coefficient between pearlite and ABS plastic plate was 0.28, the collision recovery coefficient between Notopterygium grain was 0.31, the collision recovery coefficient between pearlite was 0.14, the collision recovery coefficient between Notopterygium grain and pearlite was 0.32, and the collision recovery coefficient between pearlite and Notopterygium grain was 0.26. The rolling friction coefficient of Notopterygium seeds was 0.043, the rolling friction coefficient of pearlite was 0.097, the rolling friction coefficient between pearlite and Notopterygium seeds was 0.037. The result curves of simulation test and field test were consistent, whereby the average relative errors were 5.6% and 3.8%, respectively, which showed that the measured physical parameters were reliable. This study provides a theoretical reference for the discrete element simulation of Notopterygium seeds and pearlite, while providing a guide for design optimization of Notopterygium seeder.

Key words: Notopterygium seeds, pearlite, EDEM, parameter calibration, stacking angle, drilling