Authors

Abstract

Using the pneumatic conveying metering technology, designed a seed-metering device with forming machine. The main work includes: the structure and working principle of metering de-vice for pneumatic conveying are expounded, carry out the dynamic analysis of flow distribution, using computational fluid dynamics software (CFD) on the flow field distribution of simulation analysis and optimize the structure parameters. The simulation results show that different blade structure parameters, which include the number, angle and arrangement order of blade have different effects on the internal flow field of the forming machine. The bench experiment of forming machine is used to verify the significance of the influence of different structural parameters and the optimal combination of parameters of the forming machine. The results showed that the filling and clearing ability of the 7-blade 10° forming machine is better than that of other groups of blade structure parameters. Increasing the angle of the blade (10° to 13°) has little effect on the flow rate difference between the filling area and the cleaning area. When the blade angles in the filling area are the same, the speed has nothing to do with the arrangement order of the blades, but the speed distribution of the cleaning area is related to the size of the blade at the end of the cleaning area. The experiment results show that when the blade size is reduced by half, the flow speed increases by about 18.9%.

Abstract in Chinese

提出气力输送式排种技术，在排种器内形成旋转气流，增强吸种和清种能力，设计了一种以气流分配室为核心的风送式排种器。主要工作包括：对气力输送式排种器的结构和工作原理进行了阐述，开展了气流分配室内流体的动力学分析，利用计算流体力学软件（CFD）对气流分配室内流场进行模拟分析并优化结构参数，通过自制的试验装置，以不同数量和排列形式的扇叶结构作为试验因素，以吸、清种区型孔风速为测试指标开展了气流分配室性能试验研究，试验结果表明随着气流分配室中扇叶数量的增加（7叶-10叶）清种区的平均速度呈线性下降趋势，清种区的平均速度保持不变；冲种区速度随着扇叶角度的增加而明显降低，但是冲种区与清种区平均速度差不变，当冲种区扇叶角度一直时，速度与扇叶大小无关。设计的气流分配室能够弄过优化结构参数实现气流在冲种区和排种器的速度需求，是为风送式排种器的选择提供条件，进而为小籽粒作物精量播种提供技术和装备支持。