Correlation of Loblolly Pine Drying Rates At High Temperature

Authors

  • Michael R. Milota
  • John L. Tschernitz

Keywords:

Wood drying, high-temperature drying, southern pine, kiln modeling, rates of drying

Abstract

A correlation of drying rates based on the physics of drying has been developed for plantation-grown loblolly pine at high temperatures. Flat-sawn boards, 8 ft in length, 4 in. in width, and in three thicknesses, 1, 1.5, and 2 in., were studied. At high moisture content, heat transfer is the controlling mechanism, and the predicted drying rate is a function of the air velocity and wet-bulb depression. At low moisture content, the predicted drying rate is a function of the dry-bulb temperature and the moisture content. No systematic variation in drying rate could be attributed to juvenile wood, rings per inch, or the presence of knots. The correlation is valid at dry-bulb temperatures from 180 F to 270 F, wet-bulb temperatures from 140 F to 200 F, and air velocities from 700 to 1,900 ft/min. This correlation can be used for modeling the effect of kiln operating parameters on the final moisture content variation and temperature drop across the load.

References

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Published

2007-06-22

Issue

Number 3 / July 1990

Section

Research Contributions

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