基于DEM-CFD耦合的玉米气吸式排种器仿真与试验
作者:
作者单位:

作者简介:

通讯作者:

中图分类号:

基金项目:

国家重点研发计划项目(2017YFD0700703)、国家自然科学基金项目(51575515)和国家玉米产业技术体系建设项目(CARS-02)


Simulation and Experiment of Corn Air Suction Seed Metering Device Based on DEM-CFD Coupling Method
Author:
Affiliation:

Fund Project:

  • 摘要
  • |
  • 图/表
  • |
  • 访问统计
  • |
  • 参考文献
  • |
  • 相似文献
  • |
  • 引证文献
  • |
  • 资源附件
  • |
  • 文章评论
    摘要:

    针对DEM-CFD计算量大的问题,首先利用Fluent仿真,通过设计进气口位置的三因素三水平正交试验,以充种区型孔压强、自清种区型孔压强、清种区型孔压强、携种区型孔压强为评价指标,进行极差和方差分析,确定最佳进气口位置参数;其次,基于离散单元法理论建立玉米籽粒黏结颗粒Bonding模型,对气道流场划分结构化网格,并设置相关参数,实现玉米气吸式排种器DEM-CFD气固耦合仿真;提取排种盘吸附玉米种子时的型孔流场压强,发现每个区域的压强都能稳定过渡,且压强由大到小为充种区、自清种区、清种区、携种区、卸种区;通过理论计算得出吸附压强最小值,并与仿真结果进行对比,结果表明仿真结果均大于理论计算吸附压强最小值;采用第1代常规气室结构排种器和本文设计排种器进行风压测定对比试验分析,验证了所选进气口位置参数的合理性;最后,以改变排种盘转速为例,选取排种器常用作业速度8、10、12、14km/h,以合格指数、重播指数、漏播指数为排种性能评〖JP2〗价指标,通过仿真考察其排种性能,并与台架试验进行对比。结果表明,在仿真模拟中,当作业速度不大于14km/h、〖JP〗负压为3kPa时,合格指数均不小于89.7%,漏播指数不大于7.8%,重播指数不大于2.5%;台架试验中,在相同的作业速度和负压下,粒距合格指数均不小于90.3%,重播指数不大于2.7%,漏播指数不大于7%;仿真试验与台架试验结果较为接近,验证了仿真模拟的可行性。

    Abstract:

    In order to solve the problem of large amount of DEM-CFD calculation, the Fluent simulation was firstly used and threefactor threelevel orthogonal test of the position of the air inlet was designed. The mean of pressure in seed filling area holes, mean of pressure in self cleared area holes, mean of pressure in clearing seed area and pressure of other holes were taken. The mean value was the evaluation index, the range and variance analysis were carried out to determine the optimum inlet location parameters. Secondly, the Bonding model of corn grain adhesive particles was established. The structure grid of the airways flow field was divided and the relevant parameters were set up to realize the DEM-CFD gas solid coupling simulation of corn gas suction seed metering device. The pressure of the plate holes was extracted from the flow field when the corn seeds adsorbed. It was concluded that the pressure changes in each region were stable, and the pressure ranges from large to small was filling area, self cleaning area, clear seed area, seed carrying area and seed unloading area. Through theoretical calculation, the minimum pressure of adsorption was obtained, which was compared with the results obtained by simulation. The results showed that the simulation results were higher than the theoretical calculation of the minimum adsorption pressure. The first generation of conventional chamber structure seed metering device and the designed seed metering device were used to test and analyze the air pressure, which verified the rationality of the selected inlet position parameters. Finally, by changing the speed of the plate, the common operating speed of the seed metering device was 8km/h, 10km/h, 12km/h and 14km/h, and the qualified index, multiple index and missing index were used to evaluate the performance of seed metering performance under different conditions by simulation test, and the comparison was carried out through the bench test. The results showed that in the simulation test, when the operation speed was not more than 14km/h and the negative pressure was 3kPa, the qualified index was not less than 89.7%, the missing index was less than 7.8% and the multiple index was less than 2.5%. In the bench test, under the same operating speed and negative pressure value, the seed spacing qualified index can reach 90.3%, the multiple index was less than 2.7%, and the missing index was less than 7%. The simulation test was close to the bench test, which verified the feasibility of the simulation.

    参考文献
    相似文献
    引证文献
引用本文

丁 力,杨 丽,武德浩,李东毅,张东兴,刘守荣.基于DEM-CFD耦合的玉米气吸式排种器仿真与试验[J].农业机械学报,2018,49(11):48-57.

复制
分享
文章指标
  • 点击次数:
  • 下载次数:
  • HTML阅读次数:
  • 引用次数:
历史
  • 收稿日期:2018-07-15
  • 最后修改日期:
  • 录用日期:
  • 在线发布日期: 2018-11-10
  • 出版日期: 2018-11-10