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Stresses in dried wood. Modelling and experimental identification

  • Stefan Jan Kowalski
  • Anna Smoczkiewicz-Wojciechowska
Chapter

Abstract

The paper presents a simple mathematical model of drying that permits evaluation of moisture content distribution in dried wood during the constant and falling drying rate periods and, in particular, estimation of stresses generated from the moment when the moisture content at the body surface reaches the fibre saturation point (FSP). The acoustic emission method (AE) is used for monitoring the state of stress in dried wood. The numerically evaluated drying induced stresses are compared with the number of acoustic signals and their energy monitored on line during drying tests. It can be stated that the enhanced emission of acoustic signals occurs at those moments when the drying induced stresses approach their maximum. Both the numerical calculus and the experimental tests were conducted on a pine-wood sample in the form of a disk.

Keywords

Shrinkage Stresses Destruction Modelling Acoustic emission 

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Copyright information

© Springer Science+Business B. V. 2006

Authors and Affiliations

  • Stefan Jan Kowalski
    • 1
  • Anna Smoczkiewicz-Wojciechowska
    • 1
  1. 1.Institute of Technology and Chemical EngineeringPoznań University of TechnologyPoznańPoland

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