Drying Douglas-fir Lumber: a Computer Simulation

Authors

  • Helmuth Resch
  • Hoyang Kang
  • Michael L. Hoag

Keywords:

Drying, computer simulation, moisture measurement, Douglas-fir lumber

Abstract

Three experimental kiln runs were designed to investigate how well the drying rate of 2-inch-thick lumber from Douglas-fir heartwood can be simulated by Hart's computer model. Simulated data were compared with gravimetric records and with electrical measurements obtained using the moisture-monitoring system designed by Forrer. This thermomoisture meter proved useful in continuously measuring moisture gradients and temperatures in boards. The first step of the computer simulation showed how diffusion coefficients varied with moisture content; however, two adjustments of the computer inputs were needed to arrive at good agreement between simulated and observed drying rates.

It was concluded that Hart's computer simulation programs and Forrer's thermomoisture meter are excellent tools for future lumber drying research and improvement of kiln schedules.

References

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Published

2007-06-22

Issue

Number 3 / July 1989

Section

Research Contributions

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