玉米全膜双垄沟气动直插式穴播机设计与仿真

玉米全膜双垄沟播农艺技术抗旱、增产,实现其机械化膜上播种将是必然趋势。依据玉米全膜双垄沟农艺技术要求,设计了气动直插式穴播机,对作业机关键作业参数进行了设计计算,并结合STEP控制函数对其播种运动轨迹进行仿真分析。为揭示气动播种单体成穴器与种床土壤互作机理,借助ABAQUS有限元法构建了成穴器与种床土壤互作三维模型,分别获得了对应的Mises应力云图、空间位移云图和塑性应变云图。仿真结果分析表明:在相同的气动直插播种作用力下,锥形成穴器与种床土壤互作应力最大值约为1.541 MPa,是楔形成穴器与种床土壤最大值的1.39倍;在相同的载荷与分析步时间内,锥形成穴器对种床土壤作业下的最大塑性变形量约为19.35mm,楔形成穴器对种床土壤的最大塑性变形量约为12.35 mm。因此,锥形成穴器较楔形成穴器形成播种穴孔的能力及动土量效果更好。研究结果将为西北旱区玉米全膜双垄沟机械化播种装置的研发提供参考。

Design and simulation of pneumatic direct insert hill-seeder with corn whole plastic-film on double ridges

The furrow sowing with whole plastic-film mulching on double ridges was widely used in the arid region of northwest China for its drought resisting and production increasing. The mechanical sowing on film was an inevitable trend in farming. On the basis of corn whole plastic-film on double ridges agricultural technical requirements, the pneumatic direct insert precision hill-seeder was designed. The key operation parameters of the operating machine were calculated and combined with STEP control function for the seeding trajectory simulation analysis. To reveal the interaction mechanism of pneumatic seeding unit punching opener and seedbed soil, ABAQUS finite element method was used to build the three-dimensional interactions model. The corresponding alternating stress nephogram, alternating spatial displacement nephogram and alternating plastic strain nephogram were obtained respectively. Simulation results showed,the maximum interaction stress nephogram of taper punching-opener and seedbed soil was 1.541 MPa under the same pneumatic direct insert sowing force, which was 1.39 times as much as the cuneiform punching-opener. Within the same load and analytical step time, the maximum plastic deformation of taper punching-opener and seedbed soil was 19.35 mm, and the maximum plastic deformation of cuneiform punching-opener and seedbed soil was 12.35 mm. Therefore, the taper punching opener had the better ability to form a hole and dig the soil effect than the cuneiform punching opener. The study results would provide the reference for the development of the mechanized seeding equipment for the corn whole plastic-film on double ridges in the northwest arid region of China.