(Semi-)analytical solution of Luikov equations for time-periodic boundary conditions

Modeling the Drying of Capillary-Porous Materials in a Thin Layer: Application to the Estimation of Moisture Content in Thin-Walled Building Blocks

“…As is known, phenomenological models take into account only the observed (external) properties of objects and do not take into account the internal mechanisms of phenomena, for example, the change in the moisture content of a capillary-porous material is studied without detailed analysis of moisture transfer. A detailed consideration of the transfer of mass and heat would lead to a model that belongs to a different class [8,25]. Analysis of models that do not belong to the class of phenomenological models is beyond the scope of our work.…”

“…In models of drying a material in a thin layer, it is assumed that the temperature and moisture content of the material almost does not change over its thickness. If these changes are significant, then more complex models based on differential equations in partial derivatives are used [8,13,[22][23][24][25] and numerical modeling [26,27]. To get an idea of the adequacy of model (28) from a physical point of view, it is necessary to compare it with experimental data.…”

“…The elements of wooden roofs function in conditions of cyclical effects of natural drying and humidification [5][6][7], for the diagnosis of which the considered models can be used. The same models can be adapted as a tool for studying the life cycle of building materials [8,9], thermal insulation materials and wall structures [10], as a contribution to achieving the main goal of sustainable development.…”

A discussion of “Characterization of hygrothermal properties of wood-based products – Impact of moisture content and temperature”

“…In that paper, hygrothermal properties of wood-based products were measured, including the sorption isotherm and vapour permeability of wood-fibre insulation. In the four years since that publication, these results have been referenced frequently [2][3][4][5][6][7][8][9][10][11]. The present author contends though that the study in [1] contains flaws in the measurement, calculation and presentation of the vapour permeability of woodfibre insulation.…”

“…The present author contends though that the study in [1] contains flaws in the measurement, calculation and presentation of the vapour permeability of woodfibre insulation. These have led to the wider adoption of incorrect permeabilities [2][3][4][5][6][7][8][9][10][11], which in turn have resulted in debateable claims, on the inaptitude of stationary vapour diffusion experiments [8,10] and on the importance of advection in hygroscopic ad-/desorption [9,11]. The goal of this discussion is to reveal the erroneous measurements, calculations and presentations in [1] as well as to discuss the ramifications for the investigations [2][3][4][5][6][7][8][9][10][11] making use of [1]'s outcomes.…”