Sensitivity Study of a Numerical Model of Heat and Mass Transfer Involved During the Medium-Density Fiberboard Hot Pressing Process
Keywords:
Sensitivity study, hot pressing, heat and mass transfer, finite element method, sorption models, initial moisture content, material propertiesAbstract
The objective of this work was to estimate the impact of the variability of the medium-density fiberboard mat heat and moisture transfer properties on the results predicted by a numerical model of hot pressing. The three state variables of the model, temperature, air pressure, and vapor pressure, depend on parameters describing the material properties of the mat known with a limited degree of precision. Moreover, different moisture sorption models and initial moisture contents also have an impact on the numerically predicted results. In this sensitivity study, we determined the impact of variations of the mat properties, sorption models, boundary conditions, and initial MC on the state variables. Our study shows that mat thermal conductivity, convective mass transfer coefficient of the external boundary, and gas permeability have the most significant impact on temperature, gas pressure, and MC within the mat. On the other hand, the convective heat transfer coefficient of the external boundary has no impact on the state variables. The sorption model affects significantly mat MC predictions only. The initial MC of the mat has a strong influence on the internal gas pressure.References
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