Design optimization and aerodynamic investigations of air suction seed metering systems through CFD-DEM approach

Abstract

The current study focuses on the design optimization of air-suction seed metering devices for precision agriculture. The effect of vacuum pressure, suction hole diameter, and seed disk speed on the performance of a metering system for corn precision seeder was investigated using the Computational Fluid Dynamics (CFD) approach. The key parameters were modeled and optimized using both single-factor analysis and response surface methodology. The results highlighted the critical role of suction holes in generating rapid pressure drops, facilitating efficient seed pickup and adhesion. The velocity and pressure contours indicated that well-optimized settings ensure stable suction, smooth airflow, and accurate seed handling. The optimal parameter combination comprising vacuum pressure of 3 kPa, suction hole diameter of 4 mm, and seed disk rotation speed of 30 RPM achieved the maximum pressure difference and improved system stability. This combination was further validated using CFD-DEM coupling for a single seed. The analysis revealed that the proposed design not only minimizes seed-to-seed interference but also improves precise seeding. The study optimized the air-suction precision seeder by conducting a single-factor analysis to determine the optimal ranges for vacuum pressure, operating speed, and suction hole diameter. The orthogonal factor testing further refined the parameters, resulting in a 3.5 kPa vacuum pressure, 7 km/h operating speed, and a 4 mm suction hole diameter as the optimal combination. The bench test results confirmed the accuracy of the optimization with M₁ = 95.98%, M₂ = 1.5%, and M₃ = 2.52%. This research provides a foundation and strong justification for improving air-suction seed metering systems, thereby significantly enhancing precision seeder efficiency and crop productivity.