Design and test of a rotary centrifugal granular fertiliser hole-applied discharge device

Abstract

To solve the issues of inadequate loading and hole formation performance of the fertiliser hole-applied discharge device, a rotary centrifugal granular fertiliser hole-applied discharge device (RCGF-HDD) was proposed, and the key components were designed through theoretical analysis. The discrete element method was used to simulate the characteristics of loading and hole formation. Bench tests were designed to validate the simulation results and to explore the adaptability of the discharge device to various types of fertiliser. Through response surface analysis, the loading and hole formation performance were found to be optimal at a fertiliser cavity depth of 21.6 mm, a forward speed of 3.6 km h⁻¹, and a fertiliser dosage per hole of 5.3 g, resulting in average hole length, coefficient of variation of hole length, and error in fertiliser dosage per hole of 72.4 mm, 8.91 %, and 1.24 %, respectively. The results of the bench test showed that under the optimal parameter combination, the average fertiliser cluster length was 22.2 mm, the coefficient of variation was 7.88 %, and the error in fertiliser dosage per hole was 5.86 %. At forward speeds of 8–12 km h⁻¹, the average fertiliser cluster length was lower than 50.0 mm, which indicated that the RCGF-HDD had a certain degree of adaptability and good fertiliser agglomeration properties. The innovative RCGF-HDD developed can meet the demand, and the research methods and results can serve as references for the design and optimisation of fertiliser hole-applied discharge devices.