An Estimation of Heating Rates in Sub-Alpine Fir Lumber


  • Liping Cai


Heat-treatment, heating rate, mass transfer


The objectives of this research were to explore the effects of moisture content on heating rates in subalpine fir lumber and to develop a user-friendly computer program to predict heating times during heat-treatment. A correction factor ϵ that can adjust the mass transfer coefficient based on the change of the moisture content was determined through the experiments. When moisture content, density, lumber size, initial and target temperatures, air velocity, dry-bulb and wet-bulb temperatures of the kiln are entered, the change of temperature with time can be predicted by the program. The results from the experiments and the data of previous publications confirmed that the program can be used to estimate heating times not only for sub-alpine fir, but also for other species. The results also indicated that heating wood with higher moisture content requires more energy and longer time than that with lower moisture content.


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