Authors

Abstract

To solve problems of non-adjustable fertilizer and low fertilization precision in the precision hole fertilization of dry direct-seeding rice, an adjustable socket-wheel precision hole fertilizer apparatus for rice was designed. The basic structure and working principle of the fertilizer apparatus were expounded, the structural parameters of key components were determined. The numerical simulation experiments based on the discrete element method were carried out by using sulfurized urea as the research object. Selecting the rotation speed of the socket-wheel, the length of the trough, the depth of the socket as the experimental factors, and taking the average amount of fertilizer discharging and the coefficient of variation of fertilization uniformity as evaluation indicators, the orthogonal rotation combined experiments with three factors and five levels were carried out. A multi-objective optimization method was used to determine the best parameter combination under the constraint of the target value of the hole fertilizer discharging of 1.500 g. The simulation results show that the coefficient of variation of fertilizer uniformity was the smallest and the coefficient of variation was 15.80% when the rotation speed of socket-wheel was 26.57 r/min, the length of the trough was 5.36 mm and the depth of socket was 5.64 mm. By using slow-release urea, sulfurized urea and bio-organic fertilizer as test materials, the bench test and field test was carried out on the fertilizer apparatus and the reliability of the simulation results and the adaptability of the fertilizer apparatus were verified.

Abstract in Chinese

针对旱直播水稻精量穴施肥中存在施肥量不可调节、施肥精度低等问题，设计了一种可调窝眼轮式水稻精量穴施排肥器。阐述了排肥器基本结构与工作原理，确定了关键零部件结构参数。以加硫尿素为试验材料，利用离散元法，选取窝眼轮转速、料槽长度、窝眼深度为试验因素，以排肥量均值、排肥均匀性变异系数为评价指标，进行3因素5水平正交旋转组合试验。在穴排肥量目标值为1.500 g的约束条件下，确定了最佳参数组合。仿真结果表明：在窝眼轮转速为26.57 r/min、料槽长度为5.36 mm、窝眼深度为5.64 mm时，排肥均匀性变异系数最小，变异系数为15.80%。以缓释尿素、加硫尿素、生物有机肥为试验材料，对排肥器进行台架验证试验与田间施肥试验，验证了仿真结果的可靠性与排肥器的适应性。