Aiming at the problems of high impurity content in the membrane after sieving the membrane impurity mixture caused by the lack of theoretical support of the trommel screen type membrane and impurity separation device and the unreasonable setting of working parameters. The dynamic distribution of the air flow field in the sorting chamber of the trommel screen type membrane and impurity separation device and the movement of materials in the device are numerically simulated to determine the best combination of working parameters, by using computational fluid dynamics and discrete element coupling method. The airflow angle, air inlet wind speed and trommel screen speed were selected as test factors to conduct gassolid twophase flow coupling simulation test, to analyze the influence of various test factors on the air flow field in the sorting chamber and the movement of materials in the device. Taking the film content rate of the output, the film content rate of impurities and the output of residual film as evaluation indicators, a threefactor, threelevel orthogonal test was carried out. The test results were subjected to multiple regression analysis, and the best combination of working parameters was obtained through the multiobjective optimization method: the air inlet wind speed was 8.5 m/s, the airflow angle was 8°, and the trommel speed was 26 r/min. The verification tests were carried out under these conditions, the results showed that the film content rate of the output was 89.31%, the film content rate of impurities was 1.99%, and the output of residual film was 0.032 6 kg/s. The relative error between the experimental results and the theoretical optimization value was less than 7%, and the indicators were 0.87, 3.82 and 6.57 percentage points better than that before the optimization of working parameters, respectively. The study verified the feasibility of analyzing the flow field of the trommel screen type membrane and impurity separation device based on DEMCFD gassolid twophase flow coupling simulation, and provided a theoretical basis for the optimization of the operating parameters of the trommel screen type membrane and impurity separation device.

Aiming at the problem that the residual film recovered by the residual film recovery machine has high impurity content and is difficult to use, based on the principle of air separation, a film collection device with both film impurity separation and residual film collection functions is improved and designed. By analyzing the motion law of residual film and impurities, the relationship between the material characteristics and the material motion trajectory is clarified. The field test was carried out with centrifugal fan speed, distance from diaphragm to film inlet and diaphragm height as test factors and impurity content as test index. The results showed that the influence of each factor on impurity content from large to small was as follows: distance from diaphragm to film inlet, centrifugal fan speed and diaphragm height. Using the response surface diagram of DesignExpert software, the comprehensive effect analysis was carried out, and the results showed that the centrifugal fan speed was 1 974 r/min, the partition distance was 767 mm, and the partition height was 723 mm. Under these parameters, the impurity content was 6.97%. The research results can provide a basis for the research and development of residual film recovery equipment.

Aiming at the cumbersome problem of sowing depth adjustment process during the working process of the traditional peanut seeder, a sowing device can be designed to adjust the sowing depth according to the change of soil moisture content. By analyzing the motion trajectory of the pusher mechanism during the adjustment process, clarifying the relationship between the adjustment depth and the angle change of the turning arm, combined with the peanut sowing depth automatic control system, the hole sower can achieve stepless adjustment according to the change of soil moisture content during the working process of the machine. The soil moisture content range, the sowing depth and the speed of the machine are selected as the experimental factors, and the pass rate of the sowing depth is the experimental index for field testing, and the test results are analyzed by Designexpert software, and the influence of various factors on the experimental indicators is clarified, and the regression curve equation is obtained. The experimental results show that the sowing depth is well adjusted during the sowing depth control process, the soil moisture content ranges from 14%-17%, the sowing depth is set to 3.5 mm, and the machine forward speed is 4 km/h, and the sowing depth has good consistency. When the soil moisture content is 15.83%, the sowing depth is set to 3.18 mm, and the machine forward speed is 3.91 km/h, the sowing depth pass rate is 98.19% at the maximum, which meets the relevant national standards and peanut planting agronomic requirements, and provides a reference for accurate sowing of peanuts.

In order to research the influence of peanut seed shape size, hill-drop planter rotating speed, and seed extractor structure on the seeding performance of hill-drop planter, peanut seeds were divided into three levels according to the shape size.In this study, models of hill-drop planter and seeds were designed using EDEM software, which simulated seeding performance under different grades of peanut seeds at different rotational speeds and structural parameters. The simulation results showed that with the increase of the working speed, the qualification index of the hill-drop planter for all levels of peanuts showed a decreasing trend. When the working speed was greater than 40 r/min, the qualification index dropped significantly. When the working speed was rated and the dimensions of the side hole and cavity were 40 mm and 30 mm, respectively, the seed metering performance of large seeds was the best, and the qualification index was 91.37%. When the sizes of the side holes and the cavity were 32 mm and 25 mm, the seeding performance of the medium seeds was the best and qualified. The index was 93.07%.When the size of the side hole and the cavity were 28 mm and 20 mm, the seeding performance of small seeds was the best, and the pass index was 93.02%. It could be seen that the adaptability of the seed and the seed extractor affects the seeding performance. The field comparison test indicated that when the working speed of the hill-drop planter was 40 r/min, the length of the side hole of the seeder was 32 mm, and the length of the cavity was 25 mm, the seeding performance of the hill-drop planter for all levels of peanut seeds was consistent with the simulation change law. It was feasible to apply the discrete element analysis method to the hill-drop planter.This research provided a theoretical basis for the optimal design of the hill-drop planter.