Drying strategies capable of reducing the stress level of a stack of boards as defined by a comprehensive dual scale model
No hay miniatura disponible
Fecha
Autores
Título de la revista
ISSN de la revista
Título del volumen
Editor
Universidad del Bío Bío
Resumen
Descripción
During drying, stresses and deformations develop in a wood board due to shrinkage fi elds whichresult from moisture content and temperature fi eld variations. In spite of numerous works done in wooddrying modelling in the last decades, wood drying optimisation based on modelling and simulationremains far from initial expectations. Two main reasons can explain this assessment: the huge variabilityof wood and the variations in drying conditions throughout the board stack in a dryer.To address these two key problems, we used a dual scale numerical tool able to compute simultaneouslythe stress and deformation of hundreds of boards in the stack during drying. A rigorous one-dimensionalmechanical formulation, based on previous works, has been used for calculating stress and deformationduring drying. The mechanical model is fi tted into a module and then added to a dual scale (boardstack)model. This numerical tool has been used to improve the drying schedules recommended by theTechnical Centre for Wood and Furniture in France (CTBA) for spruce. The proposed drying schedulesallow the board quality to be improved. Note that the optimisation was limited to medium temperaturevalues, so that the proposed schedule can be applied to conventional kilns.
Palabras clave
Agrociencias