Radial Moisture Profiles of Cedar Sapwood During Drying: A Proton Magnetic Resonance Study


  • Jeff J. Quick
  • Joseph R. T. Hailey
  • Alexander L. MacKay


Cedar, sapwood, drying, proton magnetic resonance, imaging, moisture profiles, moisture content


The drying of 6 x 6 x 10 mm western red cedar (Thuja plicata Donn.) sapwood samples has been studied with proton magnetic resonance (1H-NMR) imaging. Bulk moisture content and one-dimensional radial moisture profiles have been observed as functions of time under controlled air flow rate and temperature conditions. The effects of these drying conditions on the behavior of bulk moisture content with time corresponded well to the effects observed in full-scale lumber drying, although typical observed drying rates were of the order of 100 times faster. Sub-millimeter resolution of the radial water distribution has been attained with moisture contents from the green state to as low as a few percent, and contrasting drying behavior has been observed in the carlywood and latewood regions of the growth rings.


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