Study on the Effect of Key Parameters of a Fertilisation Device on Fertilisation Depth

Abstract

In view of the problems of the uneven spatial distribution of particle fertiliser and unstable depths of side-deep fertilisation, caused by existing fertiliser application devices in fertile ditches, the influence of key factors of fertiliser application devices on the depth of fertilisation was studied, in combination with the agronomic characteristics of side-deep fertilisation for the direct seeding of rice in the middle and lower reaches of the Yangtze River. By analysing the incident mud process of fertiliser particles, the factors influencing the impact of mud resistance were determined. Through the theoretical and simulation analysis of the fertilisation device, it was determined that the impact distance, the impact surface radian and the fertiliser particle diameter have the greatest impact on the fertilisation depth of the device. Single factor and orthogonal tests were carried out, with three key factors as test factors and fertilisation depth as the test index. The test results revealed that the influence of the three factors on fertilisation depth follows the order of fertiliser particle diameter > impact distance > impact surface radian. With the maximum fertilisation depth as the objective, the optimal combination of the working parameters was identified as fertiliser particle diameter = 16.0 mm, impact distance = 56.5 mm, and impact surface radian = 29.6°. Furthermore, field tests were carried out in paddy fields with a water content of 37.00 ± 2.60%. When the fertilisation depth was pre-set as 50 mm, the relative error between the pre-set value and actual fertilisation depth was lower than 8.8%. The fertilisation depth can meet the agronomic requirements of side deep fertilisation and the results provide an important reference for the design of a non-contact fertilisation device for direct rice seeding.