锥形撒肥圆盘中肥料颗粒运动模型优化与试验

针对锥形撒肥圆盘存在抛施肥均匀性差、相关理论和解析模型研究较少等问题,建立了肥料颗粒在锥形撒肥圆盘上及空气中的运动模型。分析锥形撒肥圆盘结构和运动参数对肥料颗粒自旋性的影响,将肥料颗粒的自旋性充分考虑在整个运动过程中,进而得到影响抛撒均匀性及抛撒幅宽的主要因素。采用正交试验方案研究了叶片长度、叶片倾角、锥形撒肥圆盘转速对肥料颗粒抛撒的横向变异系数的影响。对正交试验结果进行方差和极差分析,结果表明:叶片长度为145 mm、叶片倾角为0°、锥形撒肥圆盘转速为1 200 r/min时,抛撒的横向变异系数为5.80%,满足抛施肥作业要求。该研究可提高马铃薯锥盘式撒肥机施肥作业效率,为锥盘式撒肥机的设计提供理论参考。

Optimization and Experiment of Fertilizer Particle Motion Model in Conical Spreading Disk

At present, there are few theoretical and analytical models of tapered fertilization disc in China, which cannot reach the ideal width, and the uniformity of throwing fertilization is poor. A model of the movement of fertilizer particles on a conical fertilizing disk and in air was established. Considering the influence of rotation of fertilizer particles in the whole movement process, the absolute velocity of fertilizer granules moving to the edge of the vane was analyzed, and the three-dimensional coordinate system which was thrown into the air from the edge of the vane was established. The law of movement of fertilizer particles to the air was analyzed. The main factors influencing the movement of fertilizer particles were obtained, and then the main influential factors that affected the throwing distance and throwing uniformity were obtained. These influencing factors involved the movement parameters and structural parameters, including vane length, vane inclination and disc speed. After determining these influencing factors, coefficient of variation was elected as test index, a static bench experiment was carried out by the orthogonal experiment plan, which was conducted in the Engineering College of Northeast Agricultural University in early October 2017. Static experiment referred to International Organization for Standardization (ISO) 5690 and American Society of Agricultural Engineers (ASAE) S341.2. Static test used two-dimensional collection matrix method. The collection matrix area consisted of 253 boxes, each collecting box had external dimensions of 20cm×20cm×10cm and its thickness was 4mm. The experimental results were obtained in data processing, the results showed that the influencing factors were all significant. When the length of the blade was 145mm, the inclination angle of the vane was 0°and the rotating speed of the disc was 1200r/min, the horizontal coefficient of variation of throwing was 5.80%, which met the requirements of throwing fertilizers. The research can improve the fertilization efficiency of potato and provide a theoretical reference for the design and optimization of potato manure spreader.