关键词: 冰雹, 猕猴桃, 数值模拟, 临界直径

Abstract:

To explore the impact assessment of hail on fruit, this paper took kiwi fruit as an example, calculated out the kiwi fruit damage assessment in the process of hail by ABAQUS finite element analysis, and combined with mechanical characteristics of kiwi fruit to calculate the damage in the hail process. The mechanical characteristics of kiwi fruit were surveyed and measured, and combined with hail landing speed, the force conversion relationship between kiwi fruit and hail impact process was calculated. The hail damage was analyzed by collision momentum method, the kiwi fruit critical damage diameter and index threshold were obtained. The results showed that the critical diameter of Guizhou kiwi fruit was bounded between 0.29-0.32 cm. When the diameter of the hail block was greater than the critical diameter value, the impact pressure of the hail block on kiwi fruit would break the hardness of the kiwi fruit, and make kiwi fruit pulp depression, seriously affected. When the hail diameter was less than the kiwi fruit critical diameter, the surface of kiwi fruit would not break, but would leave potholes. It was feasibility to study the hail impact by numerical simulation. According to the hail suppression characteristics and hail suppression parameters of different fruits, the planting area structure and fruit varieties could be adjusted to provide a theoretical basis for the analysis of artificial hail suppression benefits.

Key words: hail, kiwi fruit, numerical simulation, critical diameter