Experimental and Numerical Investigation of Wood Drying Process Using Modified Infra-Red Heating Treatment
Erzsébet Cserta, Chair of Thermal Process Technology, University of Leoben, Leoben, A-8700, Austria, László Könözsy, Christian Doppler Laboratory for Multiphase Modeling of Metallurgical Processes, Department of Metallurgy, University of Leoben, Leoben, A-8700, Austria, Gergely Hegedűs, Kentech Ltd., Sárgarózsa, Budapest, H-1163, Hungary, and Harald Raupenstrauch, Chair of Thermal Processing Technology, University of Leoben, Leoben, A-8700, Austria.
The infra-red heating technique of wood drying process is a relatively new reseach area. The drying process is essencial both in the biomass thermochemical conversion and in the wood industry, thus the present method seems to be an appropriate treatment. Although, many classical solution have frequently been used in the industrial sector, the time saving and energy consumption can be further decreased by developing effective technologies. The drying of organic materials is a complex engineering process concerning that the wood is a heterogeneous and anisotropic biological porous medium. The transport of mass, momentum and heat occurs simultaneously, therefore it is necessary to find an approximate mathematical solution for modeling the process. A one-dimensional model has been set up to investigate numerically the heat transfer in wood slab. The finite difference method has been used to obtain an approximate solution of the temperature profile using explicit and implicit schemes. The temperature conductivity, which is one of the most important characteristic of the material, has been taken into account based on the experimental data system. The numerically predicted results have been compared with temperature measurements concerning different process parameters (e.g. initial moisture content of the wood, heating rate, heating effect). A good agreement with experimental data were obtained.