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Licensed Unlicensed Requires Authentication Published by De Gruyter February 15, 2013

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

Per Isaksson, Per A. Gradin and Lisbeth M. Hellström
From the journal Holzforschung

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.


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

The Swedish Foundation for Knowledge and Competence Development (KK-Foundation) is greatly acknowledged for their financial support.

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Received: 2012-9-7
Accepted: 2013-1-14
Published Online: 2013-02-15
Published in Print: 2013-08-01

©2013 by Walter de Gruyter Berlin Boston

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