A CONTROL-VOLUME FINITE-ELEMENT NUMERICAL-SIMULATION OF THE HIGH-TEMPERATURE DRYING OF SPRUCE

Drying plays an important role in many industries as diverse as cement production to the manufacture of foodstuffs. In order to understand the fundamental physics of the drying operation it is necessary to study the movement of moisture, in both the liquid and gaseous phases, throughout the capillary-porous body. The insight gained from the study can lead, not only to a greater understanding of the phenomena which arise during drying, but also, to an increase in the efficiency and productivity level of the kiln. Experimental methods enable drying practitioners to gain only a limited insight, whereas, mathematical models have been shown and proven to give a more detailed analysis of the drying process. This paper presents a novel application of the control volume finite element numerical technique to simulate the high temperature drying of spruce. The numerical treatment of this problem has been studied extensively in the past, however, the basic drawback with previous numerical analyses is that they have been limited to a structured fixed mesh. During drying, timber twists and distorts and to accurately model the drying procedure, it is essential that this behaviour is taken into consideration. The control volume finite element method enables a structured or unstructured mesh to be employed without alteration to the formulation, and lays the foundation for the simulation of the timber deformation.