基于响应面法的谷子流体排种器搅拌技术参数优化

Abstract

Fluid seeding is a new technology for drought resistance, water saving and yield increase in modern agriculture. To improve the uniformity of fluid seed metering of millet, the mechanical stirring device was added to the metering device, and the single-factor tests were carried out on the size parameters of the pump tube, the installation position and the parameters of mechanical stirring. The stirring speed, the ratio between the length of stirring paddle and the diameter of seed box and distance between the pump tube and the stirring paddle were selected as independent variables, and the right rate of hill distance, right rate of seeds per hill and rate of no seed hill were selected as response values. According to the test design principle of Central Composite Design, a response surface analysis method was used to establish mathematical models between each experimental factor and performance index, and the influencing factors of fluid seed metering were analyzed. The single-factor test results showed that when the pump tube was installed on the side of the seed box, and its inner diameter and wall thickness were 4.8 mm and 1.6 mm, respectively, the seeding performance was better. The response surface test results showed that the selected factors all have an influence on the performance of millet fluid seed metering, and the optimal stirring parameters were the stirring speed of 30 r/s, the ratio between the length of stirring paddle and the diameter of seed box of 0.69, and distance between the pump tube and the stirring paddle of 0.11 cm. The verification test was conducted under these parameters, and the right rate of hill distance, right rate of seeds per hill and rate of no seed hill were 94.14%, 84.24%, and 2.21%, respectively, and the error from the predicted values was less than 4%. The performance indexes of fluid seed metering were improved compared with the fluid seed metering device without stirring device, indicating that the optimized stirring parameters can improve the performance indexes of millet fluid seed metering. This study can provide a reference for the research and development of key technologies and equipment for precision fluid seed metering of millet.