Construction and analysis of the forced vibration model of separating screen under a dropped potato

Abstract

AbstractTo determine the damage characteristics of potato falling on the separating screen and their relationship with the vibration characteristics, it is expected to provide a reference for the structural optimization of potato harvesting related machinery. The vibration characteristics of the separating screen were theoretically analyzed and a forced vibration model of separating screen was developed. The effects of vibration model parameters on the damage volume of potatoes were studied by single‐factor experiments with fall height, potato mass, fall direction, and potato varieties as experimental factors. Especially, the changes of decay coefficient α and the potato damage volume with test factors were obtained: the attenuation coefficient α increased with increasing falling height and potato mass and showed a significant correlation with potato damage volume. The decay coefficient α becomes largest when the potato falls along the length direction and smallest when it falls along the thickness direction. The α decreased with increasing hardness of potato varieties and showed a significant negative correlation with potato damage volume. Fitting equations between the attenuation coefficient α and the damage volume for each effects were established to predict the potato damage under different height, mass, and variety, as follows: V1 = 498035α − 2516, V2 = 209646α − 286, and V3 = −84397α + 1149.Practical ApplicationsDuring the mechanized harvest process, severe potato damage occurred on the swing separation screen. This will seriously affect the quality and economic value of potatoes. At present, there are few studies on the vibration damage theory and experiment during potato harvest. Therefore, in order to clarify the vibration characteristics of the separation screen and its relationship with the potato damage characteristics, we studied the influence of the vibration characteristics on the potato damage through the drop test, and established the vibration model of the separation screen. The relationship between the model parameters and the potato damage volume was further explored, and a mathematical model was developed to predict the volume of potato damage. This study provides a reference for the study of the coupled vibration of the potato soil mixture and the optimization of the potato soil separation device.