Simsor: A Computer Simulation of Water Sorption in Wood
Keywords:
Computer simulation, drying simulation, kiln drying simulation, moisture movement, sorptionAbstract
SIMSOR, a computerized simulation of sorption, represents an effort to structure the known essential physical phenomena that control the drying behavior of wood in such a way as to permit the duplication, with acceptable accuracy and cost, of experimental data obtained from actual drying studies. Programming knowledge is not required for its use. It can accurately simulate a typical red oak kiln schedule in less than one minute of computer time. It will handle adsorption or desorption, from freezing temperatures to boiling temperatures, and at humidities from virtually 100% to nearly 0%. Wood of any thickness and density, permeable or impermeable, can be simulated over any desired range of wood moisture content. However, its use to duplicate experimental data requires that the diffusion coefficient be adequately defined over the entire applicable range of moisture contents. At present, this will generally require a trial and-error approach, especially in the free water range. Free water is treated the same as bound water, but the temperature dependence may be canceled, if desired.
Although the simulation has already been proven under a variety of trials, it still needs to be tested under the widest possible range of applications. Wherever duplication of experimental data proves the validity of the simulation, it can then be used to provide a much more comprehensive analysis of wood-drying procedures and variables, and in far less time at far less cost, than is possible by actual physical trials.
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