Finite Element Analysis and Feasibility of Simple Stochastic Modeling in the Analysis of Fissuring in Grains during Soaking

A finite element analysis was conducted to determine
the effect of moisture diffusion and hygroscopic swelling in rice. A
parallel simple stochastic modeling was performed to predict the
number of grains cracked as a result of moisture absorption and
hygroscopic swelling. Rice grains were soaked in thermally (25 oC)
controlled water and then tested for compressive stress. The
destructive compressive stress tests revealed through compressive
stress calculation that the peak force required to cause cracking in
grains soaked in water reduced with time as soaking duration was
extended. Results of the experiment showed that several grains had
their value of the predicted compressive stress below the von Mises
stress and were interpreted as grains which become cracked and/or
broke during soaking. The technique developed in this experiment
will facilitate the approximation of the number of grains which will
crack during soaking.

• Jonathan H. Perez
• Fumihiko Tanaka
• Daisuke Hamanaka
• Toshitaka Uchino

• Cracking
• Finite element analysis
• hygroscopic swelling
• moisture diffusion
• von Mises stress.

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