Abstract
The equilibrium moisture contents and moisture diffusion coefficients of two types of Timber Strand® and four types of Parallam® were experimentally determined in this study. The Hailwood-Horrobin sorption model was fitted to theM e and the regression parameters that define the sorption isotherm were found to vary with material type, sorption mode and ambient temperature. An optimization technique was implemented to obtain diffusion coefficients from the experimental data. The results showed that the diffusion values of LSL and PSL were strongly affected by temperature and sorption direction relative to flake or strand orientation. Moisture content also affected the diffusion values, but the trend depended on the moisturetransfer mechanism that was dominant in the material.
Zusammenfassung
Die Gleichgewichtsfeuchte (M e) und die Diffusionskoeffizienten für zwei Typen von “Timber Strand” und vier “Parallam”-Typen wurden bestimmt. Das Hailwood-Horrobin Sorptionsmodell wurde entsprechend angepaßt. Es zeigte sich, daß die Regressions-Parameter, die die Sorptionsisotherme definieren, mit Materialtyp, Sorptions-Mode und Umgebungstemperatur variieren. Mittels einer Optimierungsstrategie konnten aus den experimentellen Daten die Diffusionskoeffizienten ermittelt werden. Die Ergebnisse zeigten, daß die Diffusionswerte von LSL und PSL stark beeinflußt sind durch Temperatur und Sorptionsrichtung in bezug auf die Spanorientierung. Die Feuchte beeinflußt die Diffusionswerte ebenfalls, hängt aber im wesentlichen vom vorherrschenden Feuchte-Transfermechanismus im Material ab.
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Cai, L., Avramidis, S. & Enayati, A.A. Moisture sorption and movement in Parallam® and Timber Strand® . Holz als Roh- und Werkstoff 55, 365–369 (1997). https://doi.org/10.1007/s001070050248
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DOI: https://doi.org/10.1007/s001070050248