Login | Create Account (DAF staff only)

Characterisation of wood properties and transverse anatomy for vacuum drying modelling of commercially important Australian hardwood species.

Redman, A.L. (2009) Characterisation of wood properties and transverse anatomy for vacuum drying modelling of commercially important Australian hardwood species. Technical Report. PG08.5097. Forest and Wood Products Australia.

Full text not currently attached. Access may be available via the Publisher's website or OpenAccess link.

Article URL: http://www.fwpa.com.au/images/processing/PGD100-0809_Vaccum_Drying_Dennis_Cullity_Report.pdf
Publisher URL: http://fwpa.com.au

Abstract

Characterisation and investigation of a number of key wood properties, critical for further modelling work, has been achieved. The key results were:

• Morphological characterisation, in terms of fibre cell wall thickness and porosity, was completed. A clear difference in fibre porosity, size, wall thickness and orientation was evident between species. Results were consistent with published data for other species.

• Viscoelastic properties of wood were shown to differ greatly between species and in the radial and tangential directions, largely due to anatomical and chemical variations. Consistent with published data, the radial direction shows higher stiffness, internal friction and glass transition temperature than the tangential directions. The loss of stiffness over the measured temperature range was greater in the tangential direction than the radial direction. Due to time dependant molecular relaxation, the storage modulus and glass transition temperature decreased with decreasing test frequency, approaching an asymptotic limit. Thus the viscoelastic properties measured at lower frequencies are more representative of static material.

• Dynamic interactions between relative humidity, moisture content and shrinkage of four Australian hardwood timbers can be accurately monitored on micro-samples using a specialised experimental device developed by AgroParisTech – ENGREF. The device generated shrinkage data that varied between species but were consistent (repeatable) within a species. Collapse shrinkage was clearly evident with this method for Eucalyptus obliqua, but not with other species, consistent with industrial seasoning experience. To characterise the wood-water relations of this species, free of collapse, thinner sample sections (in the R-T plane) should be used.

Item Type:Monograph (Technical Report)
Funders:Department of Primary Industries and Fisheries (DPI&F), Queensland University of Technology (QUT), AgroParisTech University - l’École Nationale du Génie Rural des Eaux des Forêts (ENGREF)
Corporate Creators:DPI&F, DEEDI
Additional Information:© Forest and Wood Products Australia.
Keywords:Vacuum drying; timber; hardwood.
Subjects:Technology > Technology (General)
Forestry
Deposited On:05 Apr 2011 07:42
Last Modified:07 Jun 2015 15:09

Repository Staff Only: item control page