论文信息 - Deformation and fracture of Macadamia nuts

Deformation and fracture of Macadamia nuts

A theoretical and numerical study of the stress distribution in nutshells being compressed between two rigid plates is presented in Part 1 of this two-part paper. An analytical solution for the contact between a spherical shell and rigid plates has been obtained based on conventional shell theories and Hertz' contact hypothesis, and the results are found to correlate very well with finite element analysis. The effect of the kernel on the deformation and fracture of complete nut-in-shells is also studied using finite element analysis, which shows that the effect of the kernel can be generally ignored as long as the shear modulus of the kernel is lower than that of the shell by two orders of magnitude. A series of tests have been conducted on Macadamia nuts, and the experimental data are discussed in terms of the stress analysis results.

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