Experiment on and simulation of moisture transfer and rolling deformation during leaf drying

ABSTRACT

The drying characteristic and rolling deformation of eaglewood leaves are investigated experimentally, and a model is built based on Fick’s law and stress–strain relations to illustrate the leaf rolling rule. The leaves dehydrate free water and hardly roll during the initial drying period. Rolling deformation is induced by the shrink difference along leaf thickness and occurs when the moisture content reaches a critical level. The rolling index of a leaf that is dried on one side is greater than that of a leaf that is dried on both sides. In addition, the rolling index is influenced by drying temperature and leaf thickness. When a leaf is thick or when the drying temperature is high, the leaf rolls considerably.

KEYWORDS:

• Leaf rolling index
• leaf rolling model
• stress–strain relation

Additional information

Funding

The authors are grateful for the support of the National Natural Science Foundation of China (No. 51076010).