Two-Dimensional Finite Element Heat Transfer Model of Softwood. Part III. Effect of Moisture Content on Thermal Conductivity
Keywords:Finite element modeling, thermal conductivity, moisture content, heat transfer, cellular structure, geometric model
AbstractThe anisotropy of wood creates a complex problem for solving heat and mass transfer problems that require analyses be based on fundamental material properties of the wood structure. Most heat transfer models for softwood use average thermal properties across either the radial or tangential direction and do not differentiate the effects of cellular alignment or differences in earlywood and latewood. A two-dimensional finite element model that considers these basic structural characteristics was developed to determine the effective thermal conductivity as a function of cell alignment, cell porosity, and moisture content. This paper extends the initial model to include moisture content effects from the oven-dry to the fully saturated condition. The model predicts thermal conductivity values as a function of density and moisture content. Comparisons are made with established empirical equations found in the literature for the thermal conductivity of wood. The models developed in this study series are useful for enhancing our understanding of fundamental heat transfer effects in various wood boards.
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