Application of a non-linear rheological model for the compaction of wood-based materials, 2th part of the research

Abstract

woodscience.hu peer-reviewed article KOCSIS, CSANÁDY (2014) The most important factors are wood species, particle size, moisture content, pressure, the rate of compression, the holding time on deformation, the diameter of the ram and the temperature of pressing. The analysis of the resulting mechanical changes during high pressure compression of wood chips in possible using non-linear rheological methods, because wood has non-linear viscoelastic properties. Consequently, during the compression process the elastic modulus of wood chips and dust increases greatly, and the resulting pellet at the end of the process suffers residual deformation. The rates of residual deformation determine the properties of the pellet, especially its density. In the present stage of our research, an approximate model was developed for the description of the force and the required length of press. The derived theoretical correlations have been verified throungh experimental results. The obtained results are useful for practical applications and contribute greatly to expanding the theoretical knowledge of wood chips and dust behavior.