基于压缩实验的酥梨果肉弹性模量和泊松比

为研究酥梨果肉的弹性模量和泊松比,制作了柱形酥梨果肉试样,开展了围压和无围压两组酥梨果肉压缩实验,得到了酥梨果肉的压力-位移曲线,通过计算获得酥梨果肉的真实应力-应变曲线、弹性模量和泊松比。当压缩应变在0~0.1范围内时,酥梨果肉的弹性模量随压缩应变呈增大趋势,而泊松比随压缩应变减小。在压缩应变为0.02、0.04、0.06、0.08和0.1时,酥梨果肉的弹性模量分别为6.19×10₅、9.63×10₅、1.28×10₆、1.56×10₆和1.81×10₆ Pa,泊松比分别为0.421、0.409、0.391、0.364和0.314。同时,建立了酥梨果肉压缩实验相应的有限元模型,对确定泊松比和弹性模量的实验方法的有效性进行了验证,对实验过程中摩擦的影响进行了分析,并应用测得的酥梨果肉弹性参数对实验过程进行了模拟,模拟得到结果实验结果符合较好。实验结果将为酥梨采摘、分选、包装和运输机械的设计提供设计依据。

Study on Elastic Modulus and Poisson"s Ratio of Pear Fruit Fruit flesh Based on Compression Experiment

In order to study the Elastic modulus and Poisson"s ratio of the pear fruit flesh, Circular-shaped samples of pear fruit flesh was prepared, Two groups of pear fruit flesh compression test of restrained and unrestrained was carried out, Obtained the pressure-displacement curve of the pear fruit flesh, and the true stress-strain curve, Elastic modulus and Poisson"s ratio were obtained by calculation. When the compressive strain is in the range of 0~0.1, the Elastic modulus of the pear fruit flesh increases but the Poisson"s ratio decreases slightly with the compressive strain. When the compressive strain is 0.02, 0.04, 0.06, 0.08 and 0.1, the Elastic modulus of the pear fruit flesh is 6.19×10₅, 9.63×10₅, 1.28×10₆, 1.56×10₆ and 1.81×10₆ Pa, the Poisson"s ratio is 0.421, 0.409, 0.391, 0.364 and 0.314, respectively. And then, The finite element model of the pear fruit flesh compression experiment was established, the validity of the experimental method for determining Poisson"s ratio and elastic modulus was verified, the effected of the friction during the experiment was analyzed, and the experimental process was simulated by using the measured elastic parameters of pear fruit flesh, the result obtained by simulation is in good agreement with the experimental results. The experimental results will provide design basis for the design of pear picking, sorting, packaging and transportation machinery.