Modeling the Continuous Pressing Process for Wood-Based Composites
Keywords:
Wood-based composites, continuous pressing, computer simulation, thermodynamics, rheology, adhesion, density profile development, product and process innovationsAbstract
The quantitative and economical importance of continuous pressing has increased steadily over the last two decades. An analytical model will be helpful in better understanding and improving this process and in developing new manufacturing techniques. Reported here is a simulation model that accounts for heat and mass transfer as well as rheological and adhesion mechanisms that occur in three dimensions as mat material passes through a continuous press. The model enables one to predict the evolution of important variables including temperature, moisture content, air and water vapor pressure, density profile, and adhesive bond strength. The scientific principles upon which the model depends are summarized along with the boundary conditions and modeling strategy employed. Model predictions are presented and discussed for a typical medium density fiberboard (MDF) production plant.References
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