A Theoretical Analysis of Timber Drying in Oscillating Climates

Abstract

Summary In this study the influence of oscillating climates on the drying of timber is investigated theoretically. First, the effect of oscillations superimposed on an ordinary drying schedule is examined by solving the corresponding partial differential equations. It is shown that the average drying rate is not affected by the oscillations. Second, properly selected oscillation amplitudes and frequencies can result in enhanced mechano-sorptive creep in the board surface layer, which enables increased external driving forces with an unchanged risk of checking. This method is analysed by using a drying simulation model. It is shown that substantial reductions in the drying time can be obtained in theory. From a practical point of view the benefit is probably rather marginal.