An Optimization Technique to Determine Red Oak Surface and Internal Moisture Transfer Coefficients During Drying


  • William T. Simpson
  • Jen Y. Liu


Kiln drying, diffusion, modeling


Lumber drying involves moisture transfer from the interior of the board to the surface, then from the surface to the surrounding air. These mechanisms can be characterized by internal and surface moisture transfer coefficients. This paper describes a least squares method, used in conjunction with standard mathematics of diffusion analysis, to determine these coefficients, resulting in good agreement between calculated and experimental drying curves.


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