水平涡轮叶片式精量排肥器设计与试验

为提高排肥均匀性，以大颗粒尿素为研究对象，设计了一种水平涡轮叶片式精量排肥器，对关键参数进行了设计与机理分析，确定了影响排肥均匀性的影响因素和参数范围，并基于离散元仿真软件确定了对数螺旋线叶片曲面参数。以涡轮叶片数量、涡轮转速和排肥口开度为试验因素，进行了排肥量的单因素试验和排肥均匀性的Box-Behnken多因素试验，结果表明，排肥量与转速呈良好的线性关系，决定系数R2不小于0.96，对于确定叶片数量的排肥涡轮，可匹配不同排肥口开度的涡轮底盘并实时控制排肥涡轮转速来调节排肥量，易于实现变量施肥作业，且排量范围内排肥均匀性较好；涡轮叶片数和排肥口开度的交互作用对排肥均匀性影响高度显著，各因素影响的主次顺序为涡轮叶片数、涡轮转速和排肥口开度；当涡轮叶片数为8个、涡轮转速为98r/min、排肥口开度为40°时，排肥均匀性系数为97.24％，实际试验验证结果与优化结果相吻合；对磷酸二胺颗粒肥料的适应性验证试验结果表明，两种颗粒肥料排肥器排肥均匀性系数接近97%，排肥量稳定性变异系数小于2%，排肥器具有较好的排肥均匀性和排量稳定性;对比分析目前常用外槽轮排肥器，设计的水平涡轮叶片式精量排肥器有效地提高了颗粒肥料的排肥均匀性。

Design and Experiment of Precision Fertilizer Distribution Mechanism with Horizontal Turbine Blades

In order to improve the fertilization uniformity performance, large granule urea was taken as the research object. A horizontal turbine blade type precision fertilizer was designed. The key parameters were designed and analyzed. The influencing factors and parameter range were determined. And based on the discrete element simulation software, the surface parameters of logarithmic spiral blade were determined. Single-factor test of fertilizer amount and Box-Behnken test of uniformity of fertilization were carried out with number of turbine blades, turbine rotation speed and angle of fertilizer hole as the main factors. The test verified that the precision fertilizer distribution mechanism with one turbine had a better row fertilizer performance which was complied with the technical specifications of fertilization machinery quality evaluation. Also, the test result showed that the fertilizer amount per second of the fertilizer distribution mechanism with one turbine was decreased with the increase of rotation speed of turbine, showing a linear relationship with a correlation coefficient larger than 0.96. Therefore, the fertilizer distribution mechanism with one turbine can adjust the fertilizer amounts by varying the rotation speeding of turbine to meet the requirements of different fertilization. Therefore, the mechanism was easy to be used on the variable-rate fertilization technology. Using Design-Expert 8.0.6 data analysis software, multiple regression analysis and response surface analysis of experimental data were carried out. The regression model between the factors and qualified rate was established and influence of factors on indexes were analyzed. The influence relation of factors on the qualified rate was determined and the order of importance was number of turbine blades, turbine rotation speed and angle of fertilizer hole in turn. Based on the regression model, the parameters were optimized and the experimental verification was worked out. Results showed that the optimal parameter combination of angle of fertilizer hole, turbine rotation speed and number of turbine blades was 40°, 98r/min and 8, respectively. The test results were consistent with the theoretical analysis results. The results of adaptability verification test for diamine phosphate granular fertilizer showed that the uniformity coefficient was close to 97%, and the variation coefficient of fertilizer output stability was less than 2%, the fertilizer had good fertilization uniformity and stability performance. The horizontal turbine blade type precision fertilizer can effectively improve the fertilization uniformity of granular fertilizer by comparative analysis with common fertilizer with external groove wheel.