Wood Science and Technology

, Volume 54, Issue 1, pp 187–201

# Two-dimensional simulation of mechanical stresses during isothermal drying of Eucalyptus nitens wood

• Carlos H. Salinas
• Cristian A. Chávez
• Natalia Pérez-Peña
• Héctor Vargas
• Rubén A. Ananías
Original

## Abstract

In this work, a two-dimensional mathematical model of the moisture transport and stress–strain phenomena during the conventional drying process of Eucalyptus nitens wood is presented. The model consists of a system of partial differential nonlinear second-order equations, where the moisture transport phenomenon is modeled on the concept of effective diffusion, and the stresses are modeled on the hypothesis of viscoelastic deformation, which is strongly linked to the strains by free contraction and mechano-sorption. The drying was assumed as an isothermal process and without effects of sustained loads over time (creep). Experimental tests were also carried out under constant psychometric conditions at 30/25 (°C/°C) in order to obtain transient distributions of moisture and stress. From these experimental data, the physical parameters of the proposed mathematical model were obtained by optimization in a context of inverse problem. The numerical solution of the model was obtained through the method of control volumes combined with finite elements. The results of transient distribution of moisture and stress correlate well with the experimental data.

## Notes

### Acknowledgements

The authors are grateful for the financial support from Fondecyt 1160812.

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© Springer-Verlag GmbH Germany, part of Springer Nature 2019

## Authors and Affiliations

• Carlos H. Salinas
• 1
• Cristian A. Chávez
• 2
Email author
• Natalia Pérez-Peña
• 4
• Héctor Vargas
• 3
• Rubén A. Ananías
• 4
1. 1.Department of Mechanical EngineeringUniversity of Bío-BíoConcepciónChile
2. 2.Department of Mechanical EngineeringUniversity of La SerenaLa SerenaChile
3. 3.Department of MathematicsUniversity of Bío-BíoConcepciónChile
4. 4.Department of Wood EngineeringUniversity of Bío-BíoConcepciónChile