An experimental study on the physical mechanics and collision characteristics of potato tubers in different haulm removal times

Abstract

Most potato harvesting in China requires haulm removal. The properties of the tubers change after haulm removal. Investigating the effects of different haulm removal times on the physical mechanics and collision damage characteristics of potato tubers during the harvest period can provide a reference for reducing the damage rate of potato tubers during mechanical harvesting. The Longshu No. 7 potato, which is widely grown in northwest China, was selected as the experimental object in this study. The tuber parameters of the physical mechanics and collision damage characteristics for four different haulm removal dates (0, 7, 10 and 14 days before harvesting) were experimentally determined. The results showed that with the increase in haulm removal time before harvesting, the rupture pressure, Young’s modulus, and shear modulus increased significantly. The coefficient of restitution decreased significantly. Additionally, when multiple potato tubers fell on the steel plate in the EDEM simulation test, the maximum force of a single tuber with the largest resultant force and the maximum contact force of all tubers were affected significantly. Both showed significant downward trends. The results of this study can provide a reference for discrete element simulation parameters related to potato harvesting machinery. It can also provide a reference for determining the time to haulm removal during the actual harvest.

Keywords

• Potato
• haulm removal time
• physical parameters
• DEM simulation