Modeling the physical processes relevant during hot pressing of wood-based composites. Part I. Heat and mass transfer

Effect of Density and Fiber Size on Porosity and Thermal Conductivity of Fiberboard Mats

“…Hot pressing is a complex process because the thickness, density and internal structure of the fiberboard mat change during compression. There is a common agreement that hot pressing of fiber mats involves two different mechanisms: Heat and mass transfer and mat rheological behavior [1][2][3][4][5]. During hot pressing, heat and mass transfer take place in the fibrous material and in the void spaces of the fiber mat.…”

3D simulation of macroscopic heat and mass transfer properties from the microstructure of wood fibre networks

“…For example, if we link the model for the transport properties to a hot-pressing model we can directly analyze the effects of fibre geometries and organization on the performance of the mat inside the hot press, and possibly on the properties of the final product. All hot pressing models for MDF and particleboard presented so far (Carvalho and Costa [26], Garcia and Cloutier [2], Thoemen and Humphrey [27]) use empirically derived expressions to describe the transport properties of the wood-furnish mat as input parameters, but do not include the simulation of these properties from the mat structure.…”

Transport Phenomena in Paper and Wood-Based Panels Production

“…In WBP hot-pressing, it is generally assumed that moisture content is below the FSP (fibre saturation point) and so water is present as vapour in cell lumens and voids between particles/fibres, and bound water in cell walls (Kavvouras, 1977;Humphrey, 1982;Carvalho et al, 1998;Carvalho et al, 2003;Zombori, 2001; Thoemen & Humprey, 2006;Pereira et al, 2006). Two main phases are then considered, the gaseous phase (air + water vapour) and the bound water; local thermodynamic equilibrium is also assumed.…”