摘要
为提高分层施肥作业中肥料分配的精确性和稳定性,实现化肥按比例分层施用,该文设计了一种气力集排式变量排肥系统分层施肥量调节装置,通过理论分析与参数计算确定了分层施肥量调节装置关键部件的结构和基本工作参数。运用离散元法与计算流体动力学耦合仿真方法,选取拨齿旋转锥的转速、入口风速和施肥速率为试验因素,以各出肥口出肥量的变异系数为试验指标,进行二次旋转正交组合仿真试验,建立了试验指标与影响因素的回归模型。在旋转锥转速735r/min、入口风速36 m/s、施肥速率0.42kg/s、分肥比例1:2条件下,对分层施肥量调节装置进行了台架试验,试验结果表明,各出肥口出肥量变异系数均小于5.18%,分肥比例误差小于2.68%,与仿真试验优化所得结果相吻合,满足施肥作业要求。研究结果可为气力集排式排肥装置的设计与优化提供技术参考与理论支撑。
Fertilizer is essential to safeguard food security, and rationalizing fertilization and improving fertilizer use efficiency can reduce its detrimental impact on environment and sustain agriculture production. Current corn fertilization in China is largely growth stage-based with a base fertilization coupled with a number of topdressings. This is inefficient in fertilizer use and labor-intensive, difficult to meet the requirements for sustainable agriculture. Delivering the fertilizer to the location in soil where the crop mostly demands for is a technology to effectively improve fertilizer use efficiency and increase crop yield. In this paper we present a pneumatic centralized device to stratifying fertilizer in soil based on the demand of crop roots. The structure and working parameters of the key components in the device were calculated theoretically;the diameter of the conveying pipe in the device was 76 mm, the inlet airflow velocity should be higher than 25 m/s, and the distribution ratio of the fertilizer can be adjusted arbitrarily from 1:1 to 1:2. The performance of the device was analyzed using the discrete element method coupled with the computational fluid dynamics by taking the rotational speed of the rotary cone(A), the inlet airflow velocity(B) and the fertilization velocity(C) as determinants, and the coefficient of variation(CV) of the fertilizer amount at each fertilizer outlet as an performance index. A quadratic-regression rotation orthogonal simulation test was used to link the performance index to the determinants. The results showed that both rotational speed of the rotating cone and the inlet airflow velocity had a significant effect on the CV. When rotational speed of the rotary cone was 735-1 196 r/min, the inlet airflow velocity was 36-41 m/s, the fertilization velocity was 0.14-0.42 kg/s and the distribution ratio was 1:2, the associated CV at different fertilizer outlets varied from 3.7% to 4.9%. The influence of all determinants on the CV was ranked in the order of A>B>C. Bench test o
作者
杨庆璐
王庆杰
李洪文
何进
卢彩云
于畅畅
娄尚易
王英博
Yang Qinglu;Wang Qingjie;Li Hongwen;He Jin;Lu Caiyun;Yu Changchang;Lou Shangyi;Wang Yingbo(College of Engineering,China Agricultural University,Beijing 100083,China;Cultivated Land Conservation Agricultural Science Observation and Experiment Station,Northern Hebei Province,Ministry of Agriculture and Rural Affairs,Beijing 100083,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2020年第1期1-10,共10页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家重点研发计划项目(2016YFD0200600)
关键词
机械化
设计
气力集排式
变量施肥
肥量调节装置
mechanization
design
pneumatic centralized
variable fertilizer
fertilizer amount adjustment device
