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Wood Research and Technology


Cellulose – Hemicelluloses – Lignin – Wood Extractives

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Volume 67, Issue 6


A numerical and experimental study regarding the influence of some process parameters on the damage state in wood chips

Per Isaksson
  • Solid Mechanics, The Ångström Laboratory, Uppsala University, Box 534, SE-751 21 Uppsala, Sweden
  • Other articles by this author:
  • De Gruyter OnlineGoogle Scholar
/ Per A. Gradin / Lisbeth M. Hellström
Published Online: 2013-02-15 | DOI: https://doi.org/10.1515/hf-2012-0142


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.

Keywords: chipping process; finite element analysis (FEA); knife angle; numerical analyses; pretreatment of chips; wood chips


  • Adina R&D, Inc. Theory and Modelling Guide. Watertown, MA, 1995.Google Scholar

  • Bathe, K.J. Finite Element Procedures. Prentice-Hall, USA, 1996.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.Google Scholar

  • Crisfield, M.A. Non-Linear Finite Element Analysis of Solids and Structures. Advanced Topics. John Wiley and Sons, UK, 1997.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.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.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.Web of ScienceGoogle Scholar

  • Dunne, F., Petrinic, N. Introduction to Computational Plasticity. Oxford University Press, UK, 2005.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.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.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.Web of ScienceGoogle Scholar

  • Hill, R. The Mathematical Theory of Plasticity. Clarendon Press, Oxford, UK, 1950.Google Scholar

  • Karlebo Handbok. Liber AB, Stockholm, Sweden, 2000 (in Swedish).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.Web of ScienceGoogle Scholar

  • Kivimaa, E., Murto, J.O. Investigations on factors affecting chipping of pulp wood. Statens Tekniska Forskningsanstalt, Finland Publ. 9, 1949.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.Web of ScienceGoogle Scholar

  • Matlab. The MathWorks, Inc., Natick, MA, 2010.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.Web of ScienceGoogle 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.Web of ScienceGoogle 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.Web of ScienceGoogle 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.Google Scholar

  • Uhmeier, A., Persson, K. (1997) Numerical analysis of wood chipping. Holzforschung 51:83–90.Google Scholar

  • Vasic, S., Stanzl-Tschegg, S. (2007) Experimental and numerical investigation of wood fracture mechanisms at different humidity levels. Holzforschung 61:367–374.Web of ScienceGoogle Scholar

  • Zienkiewicz, O.C., Taylor, R.L. The Finite Element Method, vol. 2: Solid Mechanics. Butterworth-Heinemann, UK, 2000.Google Scholar

About the article

Corresponding author: Lisbeth M. Hellström, Mid Sweden University, FSCN, SE-851 70 Sundsvall, Sweden

Received: 2012-09-07

Accepted: 2013-01-14

Published Online: 2013-02-15

Published in Print: 2013-08-01

Citation Information: Holzforschung, Volume 67, Issue 6, Pages 691–696, ISSN (Online) 1437-434X, ISSN (Print) 0018-3830, DOI: https://doi.org/10.1515/hf-2012-0142.

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