A numerical and experimental study regarding the influence of some process parameters on the damage state in wood chips
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Per Isaksson
Abstract
The specific energy consumption during mechanical refining operation can be reduced by choosing the optimal process parameters in the wood chipping process such that a beneficial pretreatment is obtained. In the case of the utilization of a larger knife-edge angle, which is one such process parameter, the energy reduction is presumably due to the increased compressive loading parallel to the wood fibers. In the present article, a chip damage parameter D of spruce is in focus, which is relevant for cracking parallel to the fibers. D is defined and its dependence on the chip length and edge angle of the chipping knife is analyzed numerically by means of finite element analyses (FEA). The cutting force was measured in a pilot wood chipper for a number of knife-edge angles. There is a good correlation between the experimental results and those of FEA.
The Swedish Foundation for Knowledge and Competence Development (KK-Foundation) is greatly acknowledged for their financial support.
References
Adina R&D, Inc. Theory and Modelling Guide. Watertown, MA, 1995.Suche in Google Scholar
Bathe, K.J. Finite Element Procedures. Prentice-Hall, USA, 1996.Suche in Google Scholar
Berg, J-E., Gradin, P.A. (2000) Effect of temperature on fracture of spruce in compression, investigation by use of acoustic emission monitoring. J. Pulp Paper Sci. 26:294–299.Suche in Google Scholar
Crisfield, M.A. Non-Linear Finite Element Analysis of Solids and Structures. Advanced Topics. John Wiley and Sons, UK, 1997.Suche in Google Scholar
Dinwoodie, J.M. (1968) Failure in timber. Part 1: microscopic changes in cell wall structure associated with compression failure. J. Int. Wood Sci. 21:37–53.Suche in Google Scholar
Dinwoodie, J.M. (1974) Failure in timber. Part 2: the angle of shear through the cell wall during longitudinal compression stressing. J. Int. Wood Sci. Technol. 8:56–67.Suche in Google Scholar
Dourado, N.M.M., de Moura, M.F.S.F., Morais, J.J.L., Silva, M.A.L. (2010) Estimate of resistance-curve in wood through the double cantilever beam test. Holzforschung 64:119–126.10.1515/hf.2010.010Suche in Google Scholar
Dunne, F., Petrinic, N. Introduction to Computational Plasticity. Oxford University Press, UK, 2005.Suche in Google Scholar
Frazier, W.C., Williams, G.J. (1982) Reduction of specific energy in mechanical pulping by axial precompression of wood. Pulp Paper Canada 83:T162–T167.Suche in Google Scholar
Frühmann, K., Burgert, I., Stanzl-Tschegg, S.E., Tschegg, E.K. (2003) Mode I fracture behaviour on the growth ring scale and cellular level of spruce (Picea abies [L.] Karst.) and beech (Fagus sylvatica L.) loaded in the TR crack propagation system. Holzforschung 57:653–660.10.1515/HF.2003.098Suche in Google Scholar
Hellström, L.M., Gradin, P.A., Engstrand, P., Gregersen, Ø. (2011) Properties of wood chips for thermomechanical pulp (TMP) production as a function of spout angle. Holzforschung 65:805–809.10.1515/HF.2011.087Suche in Google Scholar
Hill, R. The Mathematical Theory of Plasticity. Clarendon Press, Oxford, UK, 1950.Suche in Google Scholar
Karlebo Handbok. Liber AB, Stockholm, Sweden, 2000 (in Swedish).Suche in Google Scholar
Keunecke, D., Stanzl-Tschegg, S., Niemz, P. (2007) Fracture characterisation of yew (Taxus baccata L.) and spruce (Picea abies [L.] Karst.) in the radial-tangential and tangential-radial crack propagation system by a micro wedge splitting test. Holzforschung 61:582–588.10.1515/HF.2007.089Suche in Google Scholar
Kivimaa, E., Murto, J.O. Investigations on factors affecting chipping of pulp wood. Statens Tekniska Forskningsanstalt, Finland Publ. 9, 1949.Suche in Google Scholar
Landis, E.N., Navi, P. (2009) Modeling crack propagation in wood and wood composites. A review COST Action E35 2004–2008: wood machining – —micromechanics and fracture. Holzforschung 63:150–156.10.1515/HF.2009.010Suche in Google Scholar
Matlab. The MathWorks, Inc., Natick, MA, 2010.Suche in Google Scholar
Navi, P., Stanzl-Tschegg, S.E. (2009) Micromechanics of creep and relaxation of wood. A review COST Action E35 2004–2008: wood machining—micromechanics and fracture. Holzforschung 63:186–195.10.1515/HF.2009.013Suche in Google Scholar
Smith, I., Snow, M., Asiz, A., Vasic, S. (2007) Failure mechanisms in wood-based materials: a review of discrete, continuum, and hybrid finite-element representations. Holzforschung 61:352–359.10.1515/HF.2007.055Suche in Google Scholar
Stanzl-Tschegg, S.E., Navi, P. (2009) Fracture behaviour of wood and its composites. A review COST Action E35 2004–2008: wood machining—micromechanics and fracture. Holzforschung 63:139–149.10.1515/HF.2009.012Suche in Google Scholar
Svensson, B.A. Frictional studies and high rate testing of wood under refining conditions. Doctorial thesis. Mid Sweden University, Department of Natural Science, Sundsvall, 2007.Suche in Google Scholar
Uhmeier, A., Persson, K. (1997) Numerical analysis of wood chipping. Holzforschung 51:83–90.10.1515/hfsg.1997.51.1.83Suche in Google Scholar
Vasic, S., Stanzl-Tschegg, S. (2007) Experimental and numerical investigation of wood fracture mechanisms at different humidity levels. Holzforschung 61:367–374.10.1515/HF.2007.056Suche in Google Scholar
Zienkiewicz, O.C., Taylor, R.L. The Finite Element Method, vol. 2: Solid Mechanics. Butterworth-Heinemann, UK, 2000.Suche in Google Scholar
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Artikel in diesem Heft
- Masthead
- Masthead
- Review
- Novel cellulose-based composites based on nanofibrillated plant and bacterial cellulose: recent advances at the University of Aveiro – a review
- Original Articles
- Quantitative structural characterization of the lignins from the stem and pith of bamboo (Phyllostachys pubescens)
- Fractionation and characterization of lignin-carbohydrate complexes (LCCs) of Eucalyptus globulus in residues left after MWL isolation. Part II: Analyses of xylan-lignin fraction (X-L)
- Alkali consumption of aliphatic carboxylic acids during alkaline pulping of wood and nonwood feedstocks
- Improvement of kraft pulp bleaching by treatments with laccase, urea, and refining
- Development and evaluation of new curing agents derived from glycerol for formaldehyde-free soy-based adhesives in wood composites
- Formation of highly hydrophobic wood surfaces using silica nanoparticles modified with long-chain alkylsilane
- The fracture behavior of birch and spruce in the radial-tangential crack propagation direction at the scale of the growth ring
- Flatwise Young’s modulus and flatwise shear modulus of plywood measured by flexural vibration test
- A numerical and experimental study regarding the influence of some process parameters on the damage state in wood chips
- Treatment of wood with silica sols against attack by wood-decaying fungi and blue stain
- Mimicking of the strength loss in the Vasa: model experiments with iron-impregnated recent oak
- Improved heat insulation system (Mirrorpanel) for construction of wood buildings
- Meetings
- Meetings
