Separated Amount and Layered Fertilization Device for Seeders: Design and Experiment

Abstract

The fertilization capability of existing precision separated amount and layered fertilization devices is limited. To address these limitations, we designed a novel fertilization device that is incorporated in a seeder. In this study, the overall structure and working principle of a single-box double-wheel fertilizer apparatus and a diagonal double-pipe opener were analyzed, and the structural parameters of the key components of the groove wheel of the fertilizer apparatus and the scimitar of the opener were designed and optimized. Field tests were carried out with the working speed, forward speed, and effective working length as test factors, and the variation coefficients of fertilization stability, uniformity, and consistency of each line as test indexes. The influence order of the factors affecting the variation coefficients of fertilization stability and uniformity was as follows (from high to low): the forward speed, working speed, and effective length. For the consistency variation coefficient of each line, the influence order was as follows: the effective length, forward speed, and working speed. Based on the optimization analysis performed using the Design Expert 8.0.6, it is concluded that when the working speed, forward speed, and effective length were 39.94 r/min, 1.72 m/s, and 28.40 mm, respectively, the fertilization performance was optimal. The corresponding variation coefficients of fertilization stability, uniformity, and consistency were 1.21%, 15.43%, and 5.26%, respectively. These results were found to be consistent with field test results, with the fertilization performance fully meeting the requirements. To analyze the performance of the opener for layered fertilization, a field test was carried out by setting the forward speed of the device as the single factor and the variation coefficient of the fertilization depth difference for the opener as the test index. The results showed that the variation coefficient of the stratification depth difference increases with the increase in the forward speed, and the stratification requirements are met when the velocity is lower than 3 m/s. This study provides a research basis and technical reference for the design and development of precision separated amount and layered fertilization devices.