Study on Structure Design and Parameter Optimization of Diversion Rifled Feeder Based on CFD-DEM

The feeder, a critical component of pneumatic conveying and distributing fertilizer machines for cotton, significantly impacts cotton quality and yield. This study addresses the limitations of conventional feeders, namely poor delivery stability and insufficient air-fertilizer mixture uniformity, by introducing a novel feeder design incorporating guide-flow chamber vanes. Based on the structural principles of pneumatic fertilizer distribution and the theory of vortex flow feeding, the new feeder design was developed and analyzed using a CFD-DEM coupled model to simulate its operational process. Response surface methodology was employed to optimize key structural parameters, aiming to enhance both air-fertilizer mixture uniformity and fertilizer delivery stability. The optimized design features two guide vanes, a fertilizer discharge contraction angle of 23.2 degrees, and eight chamber lines. Validation through simulation confirmed the model's reliability, with a discrepancy of less than 5% between simulated and predicted values. Experimental validation on a pneumatic fertilizing test prototype further demonstrated the effectiveness of the optimization, resulting in a feeder stability coefficient of variation of 13.30% and a coefficient of variation in fertilizer distribution across the system's branches of 3.96%, satisfying practical operational requirements. After optimization, the stability and uniformity of the feeder fertilizer are significantly improved. The optimized feeder design effectively improves the stability and air-fertilizer mixing uniformity of cotton pneumatic fertilizing machines, providing valuable theoretical and technical support for their design optimization and performance enhancement.