Objective The construction method of the discrete element model and the setting of simulation parameters in the strip- and blade-shaped sugarcane leaf are unclear. The simulation model’s accuracy greatly influences the dynamic response characteristics between particles, and it is necessary to improve the accuracy of simulation parameters through parameter calibration. Method The discrete element parameters are optimized and calibrated based on the response surface methodology (RSM) with sugarcane leaf physical angle of repose as the response value. Firstly, the basic physical parameters and angle of repose of sugarcane leaves were measured by physical tests, and the simulation model of sugarcane leaf was established by the multi-sphere polymerization model and XML method. The effects of the sugarcane leaf model filled with different radii particles on the simulation angle of repose and simulation efficiency were analyzed to find the optimal filling particle size of the sugarcane leaf model. Then, a Plackett-Burman test was used to select the parameters that significantly influence the simulation angle of repose. Furthermore, the optimal value ranges of the three significant parameters were determined by a steepest ascent search test, and the second-order regression equation between the significant parameters and angle of repose was established based on the Box-Behnken test, the optimal combination of parameters was obtained with the physical angle of repose of 21.15° as the optimal target value. Finally, a gas-solid coupling simulation test was conducted with the trash content as the test index and compared with the field test. Result The optimal filling particle size of the sugarcane leaf simulation model was 2 mm. The optimal combination of significant parameters was as follows: the static and rolling friction coefficients between sugarcane leaves were 0.21 and 0.05, respectively, and the static friction coefficient between sugarcane leaves and steel was 0.30. There was no significant difference between the simulation value and the test value of trash content, and the maximum relative error between them was 8%, which further showed that the parameter calibration of the sugarcane leaf model was reliable. Conclusions The results showed that the modeling method and parameter calibration of the sugarcane leaf model was accurate and reliable and could be used for subsequent gas-solid coupling simulation research, as well as providing a reference for the calibration of the discrete element parameters of the strip-and blade-shape materials.

The seed filling of a seed-metering device is a critical process in sugarcane cultivation operations. To analyze the contact between billets, the related mechanical components, and the law of billets movement in the seed-metering device, a simulation of the seed-filling process based on EDEM was proposed, and a geometric model of the seed-metering device, a particle model, and a contact model were established by EDEM software. The physical experimental results and simulation results of the angle of repose were compared. The experimental results showed that the relative error of the angle of repose experiment was 6.67%, which verified the effectiveness of the material parameters of single-bud billet; the linear correlation coefficient of the seed-filling experiment was 0.762 for S_q and 0.869 for S_e, which demonstrated the validity of using EDEM software to simulate the seed-filling process. Finally, the velocity and force of the particles in the seed-filling process were analyzed in EDEM. The analysis results indicated that there are two circulation circles in the seed box, and the larger the circulation circle, the easier the billets enter the rake bar. The EDEM simulation provides a basis for optimizing the structure and parameters of the sugarcane billet planter in future work.

The cleaning system is a critical component of the sugarcane chopper harvester, facing challenges such as high impurity rate, elevated power consumption, and an inadequate understanding of the cleaning mechanism. This study aims to simulate the process of removing extraneous matter (represented by sugarcane leaves) from the cleaning system by employing a coupling approach of computational fluid dynamics (CFD) and the discrete element method (DEM) to determine the speed of the extractor fan. Initially, a CFD model was established to analyze the airflow field within the extractor, and its accuracy was verified on a test bench for the cleaning system. Subsequently, a DEM model was developed for sugarcane billets and leaves, which was then integrated with the CFD model to form a gas–solid coupling model. The efficacy of this integrated model was confirmed through experimental measurements of impurity rate. Furthermore, a ternary quadratic regression orthogonal combination design was utilized in the gas–solid coupling simulation to assess the impacts of feed rate, leaf–stalk ratio, and extractor fan speed on impurity rate. Finally, the extractor fan speeds were obtained for various feed rates and leaf–stalk ratios under impurity rates of 5%, 6%, 7%, and 8%. This research can guide in controlling the extractor fan speed during sugarcane chopper harvester field operations and can serve as a foundation for extractor fan design.

Planting uniformity is a key evaluation index for planters. This paper investigated the effect of rotational speed, the angle of the rake bar chain, and the number of billets on the planting uniformity of a seed-metering device in the laboratory. The experimental results showed that the optimal planting uniformity can be achieved under a rake bar chain angle of 117°, a number of billets of 500, and a rotational speed of the rake bar chain of 70 rpm. Under this condition, the quality index Z_q was 97.22% and the multiple index Z_m was 0%, while the miss index Z_e was 2.78%. Based on the above parameters, a single-bud planter was improved with three rake bar chains per seed box. Field experiments with different operation parameters (rotational speed, forward speed) were conducted. Results indicated that when the rotational speed was 40 rpm and the forward speed was 2.26 km/h, the planting uniformity was the best and the quality index Z_q was 93.38%. The research results provide a basis for the application of single-bud billet planters in the field.