Design And Performance Test Of Sunflower Seed Directional Adsorption Seed-metering Device

In response to the problem of varied adsorption orientation and poor stability of seeds during the operation of pneumatic planters for sunflower sowing,which leads to a decline in seeding quality and fails to meet the requirements of agronomic practices.This article proposes a method of utilizing mechanical structures to assist in stabilizing the adsorption posture,in order to design and optimize key components of a sunflower seed directional adsorption planter.Fit the contour parameter equation based on the size of the seed’s outer shape.By means of theoretical analysis and numerical simulation,the motion mechanism of seeds is analyzed and a mechanical model for seeds is established.By means of discrete element and airflow field simulation,the movement laws of the seed population and the distribution of the airflow field are determined.By conducting indoor bench tests,the influence of different working and structural parameters on the seeding performance is explored,and an optimal parameter combination is sought.The main research of this thesis is as follows:1.Taking sunflower seeds as the research object,the physical Parameters were measured,and the sunflower seed shape Parameter equation was established by extracting the sunflower seed shape profile;based on the sunflower seed shape Parameter equation,the sunflower seed discrete element model was established;through the Parameter calibration test,the rest angle was used as the response value to optimize the simulation Parameters of sunflower seeds.2.Through the method of mechanical structure-assisted stabilization of the adsorption attitude,the key components of the seed dispenser,such as the seed disks,seed stirring devices,seed cleaning devices and seed adjust devices,are designed and optimized to improve the seed filling efficiency,adjust the seed adsorption attitude and increase the stability of seed adsorption.3.The mechanical analysis of seed adsorption process was carried out to establish the mechanical equation of seed adsorption and derive the key Parameters affecting the stability of adsorption;the discrete element simulation was used to analyze the population movement law;the airflow simulation was used to analyze the influence of working Parameters on airflow.4.Based on the results of the single-factor test,it was determined that the seed-metering plate rotation,the critical vacuum at the suction hole,the length,width and depth of the suction groove and the deflection angle all had significant effects on the performance of the seeding.5.Different structural Parameters(length,width and depth of the seed suction groove)and working Parameters(rotational speed of the seed discharge disc and critical vacuum degree at the suction hole)were used as test factors,and the qualified index,multiple index and missed index were used as evaluation indexes.The performance was better when the rotational speed of the seeding plate was 11.58 r/min,the vacuum degree was 0.7 Kpa,the width of the suction groove was 10.5 mm,the depth was 3 mm and the length was 23 mm,and the qualified index was 91.63%,the multiple index was 5.63%and the missed.