Abstract
Numerical analysis of temperature profiles during thermal modification of wood was carried out. The numerical solution – based on finite element analysis, FEA – of the 3D problem of transient nonlinear heat transfer model is presented for wood as a typical anisotropic material. The numerical model was enhanced for describing chemical reactions of cellulose, hemicelluloses and lignin (pyrolysis model), which takes into account the exothermic reactions as an internal source of heat energy. Experimental as well as theoretical process schedules were applied and the influence of sample dimensions (sample geometry) and wood species was studied. The influence of wood species was negligible on heating time to reach the highest temperature, i.e., the temperature differences were about 2°C during the drying phase. A expected, the sample size played an important role in the heating duration and in terms of the exothermic reactions of wood. The experimental and numerical data are generally in good agreement. The numerical error increased in the range of higher temperatures. The results can be improved by consideration of wood species (mass of wood compounds) and boundary conditions in the pyrolysis model, thus, better insight into details of thermal modification of wood could be reached.
Acknowledgments
This work was supported by OP Education for Competitiveness (European Social Fund and the state budget of the Czech Republic) CZ.1.07/2.3.00/30.0017 Postdocs in Biological Sciences at MENDELU; CZ.1.07/2.3.00/30.0031 Postdocs in Technical and Economical Sciences at MENDELU and project “The Establishment of an International Research Team for the Development of New Wood-based Materials” reg. no. CZ.1.07/2.3.00/20.0269.
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©2015 by De Gruyter
Articles in the same Issue
- Frontmatter
- Original Articles
- Characterization of dissolved lignins from acetic acid Lignofibre (LGF) organosolv pulping and discussion of its delignification mechanisms
- Organic materials in black liquors of soda-AQ pulping of hot-water-extracted birch (Betula pendula) sawdust
- Effects of concentration and temperature on the rheological behavior of concentrated sodium lignosulfonate (NaLS) solutions
- Raman microscopic analysis of wood after treatment with the ionic liquid, 1-ethyl-3-methylimidazolium chloride
- Isolation and structural elucidation of norlignan polymers from the heartwood of Cryptomeria japonica
- Effect of ball milling on lignin polyesterification with ε-caprolactone
- Property enhancement of kenaf fiber composites by means of vacuum-assisted resin transfer molding (VARTM)
- Wood polypropylene composites prepared by thermally modified fibers at two extrusion speeds: mechanical and viscoelastic properties
- Numerical analysis of temperature profiles during thermal modification of wood: chemical reactions and experimental verification
- Fast online NIR technique to predict MOE and moisture content of sawn lumber
- Numerical study of the influence of veneer lathe checks on the elastic mechanical properties of laminated veneer lumber (LVL) made of beech
- Amination of pretreated ayous (Triplochiton scleroxylon) sawdust with two organosilanes: characterization, stability, and permselective property
- Damage evolution in wood – pattern recognition based on acoustic emission (AE) frequency spectra
- Mechanical stability of superhydrophobic epoxy/silica coating for better water resistance of wood
- Short Note
- Urea-formaldehyde resin penetration into Pinus radiata tracheid walls assessed by TEM-EDXS
- Obituary
- Professor Dr. Arnis Treimanis
Articles in the same Issue
- Frontmatter
- Original Articles
- Characterization of dissolved lignins from acetic acid Lignofibre (LGF) organosolv pulping and discussion of its delignification mechanisms
- Organic materials in black liquors of soda-AQ pulping of hot-water-extracted birch (Betula pendula) sawdust
- Effects of concentration and temperature on the rheological behavior of concentrated sodium lignosulfonate (NaLS) solutions
- Raman microscopic analysis of wood after treatment with the ionic liquid, 1-ethyl-3-methylimidazolium chloride
- Isolation and structural elucidation of norlignan polymers from the heartwood of Cryptomeria japonica
- Effect of ball milling on lignin polyesterification with ε-caprolactone
- Property enhancement of kenaf fiber composites by means of vacuum-assisted resin transfer molding (VARTM)
- Wood polypropylene composites prepared by thermally modified fibers at two extrusion speeds: mechanical and viscoelastic properties
- Numerical analysis of temperature profiles during thermal modification of wood: chemical reactions and experimental verification
- Fast online NIR technique to predict MOE and moisture content of sawn lumber
- Numerical study of the influence of veneer lathe checks on the elastic mechanical properties of laminated veneer lumber (LVL) made of beech
- Amination of pretreated ayous (Triplochiton scleroxylon) sawdust with two organosilanes: characterization, stability, and permselective property
- Damage evolution in wood – pattern recognition based on acoustic emission (AE) frequency spectra
- Mechanical stability of superhydrophobic epoxy/silica coating for better water resistance of wood
- Short Note
- Urea-formaldehyde resin penetration into Pinus radiata tracheid walls assessed by TEM-EDXS
- Obituary
- Professor Dr. Arnis Treimanis