Calibration of the Phloem–Xylem Static Friction Coefficient

Based on the physical measurement results of the phloem–xylem static friction coefficient, discrete element simulation tests with the same experimental conditions were established. The friction test set the incline angle of the phloem plate to rise at a speed of 10 deg/s with a time step of 20% of the Rayleigh time and a save interval of 0.001 s. The sliding angle was obtained by reading the data through the discrete element analyst module.

#### Calibration of the Phloem–Xylem Rolling Friction Coefficient

Based on the physical measurement results of the phloem–xylem rolling friction coefficient, discrete element simulation tests with the same experimental conditions were established. The friction test set the incline angle of the phloem plate to rise at a speed of 10 deg/s with a time step of 20% of the Rayleigh time and a save interval of 0.001 s. The rolling angle was obtained by reading the data through the discrete element analyst module.
