Authors

Abstract

The mechanical parameters of Cerasus humilis are the basic data for subsequent studies on fruit deformation, damage, and movement characteristics during harvesting and transportation, but these parameters are rarely reported. Relevant mechanical parameters of whole fruit compression are calculated by comparing physical tests and virtual simulations. The orthogonal rotating combined experimental design was used to arrange the simulation tests, with the elastic modulus (E), yield limit (Ey), and tangent modulus (Et) as the influence factors and compression force as the result. Response surface optimization was employed to find the closest test point to the force–deformation curve of the physical test. The parameters of the pulp test point are as follows: E = 0.923 MPa, Ey = 0.0897 MPa, and Et = 0.478 MPa. Results show that the step on the force–deformation curve was not the beginning of the pulp yield, which was substantially earlier than the strain rate at the simulation step. The region of increased stress in the pulp first appeared at the junction with the core due to stress concentration. Combining virtual and physical tests to solve the mechanical parameters of fruits is more suitable than testing the standard pulp sample.

Abstract in Chinese

钙果的力学参数是后续研究果实在采收和运输过程中变形、损伤和运动特性的基础数据，但这些参数的报道很少。通过物理试验和虚拟仿真的结合，计算了全果压缩的相关力学参数。采用正交旋转组合试验设计，以弹性模量(E)、屈服极限(Ey)和切线模量(Et)为影响因素，压缩力为结果，设计了虚拟试验方案。采用响应面优化方法，寻找最接近物理试验力–变形曲线的试验点。果肉测点参数为:E = 0.923 MPa, Ey = 0.0897 MPa, Et = 0.478 MPa。结果表明:果肉屈服的起始点并非力–变形曲线上的阶跃点，而是明显早于阶跃点的应变率。由于应力集中，果肉中应力增加的区域首先出现在与果核的交界处。将虚拟试验和物理试验相结合来求解水果的力学参数，比测试标准果肉样品更合适。