Analysis of Breaking and Separating Characteristics of Potato–Soil Aggregates Based on the New Type of Swing Separation Sieve

Abstract

In response to the significant challenge posed by the trade-off between the efficiency of separating potato soil and minimizing potato peel damage in the 4SW-170 potato excavator, this study focused on enhancing the design of the swing separation sieve. The objective was to develop a novel separation sieve comprising three distinct orders of sieve surfaces. Building upon this foundation, the EDEM-Adams coupled simulation method was employed to explore the fragmentation and separation attributes of potato–soil aggregates. This investigation aimed to elucidate the behavior of potato–soil aggregates within the operational scope of the novel swing separation sieve. Subsequently, the optimized parameters were validated through field tests. The findings indicate a direct correlation between the fracture ratio of the cohesive bond and the crank speed, illustrating an increase in the former with higher crank speeds. Conversely, an inverse relationship exists between the fracture ratio and the sieve inclination angle, demonstrating a decrease in the ratio as the sieve inclination increases. At a machine speed of 1.9 km/h, the fracture ratio of the cohesive bond attains its peak value. The force exerted on potatoes at their maximum point escalates with rising crank speed but diminishes with increasing machine speed. Conversely, the effect of sieve inclination on the peak force applied to the potatoes is deemed inconsequential. The most effective parameter configuration for the separation sieve comprises a crank speed of 180 revolutions per minute (r/min), a machine speed of 1.9 km per hour (km/h), and a sieve inclination of 14.4°. Field trials have confirmed that the parameter combination yielded a potato detection rate of 98.01% and a mere 0.68% rate of potato skin breakage, meeting the stipulated technical specifications of the potato harvester.