Open AccessSteady-state and unsteady-state moisture regime of enclosing structure
Author(s) -
Vladimir G. Gagarin,
Pavel Khavanov,
Kirill Zubarev
Publication year - 2020
Publication title -
iop conference series. materials science and engineering
Language(s) - English
Resource type - Journals
eISSN - 1757-899X
pISSN - 1757-8981
DOI - 10.1088/1757-899x/896/1/012015
Subject(s) - moisture , work (physics) , steady state (chemistry) , mechanics , state (computer science) , water content , environmental science , materials science , computer science , mechanical engineering , engineering , geotechnical engineering , physics , chemistry , composite material , algorithm
This paper describes the moisture transfer problems of enclosing structures which are crucial in modern construction industry. In terms of current condition of science, researchers do not know the moisture transfer law in capillary-porous materials, so they need to work with a variety of mathematical models. We developed the new steady-state and unsteady-state formulation of mathematical models based on moisture potential F, which takes into account water vapour and liquid movements uniformly. It is vital to understand whether we can use steady-state moisture transfer mathematical model in a design engineer work or we must use the unsteady-state one, so we make a comparison between them for a single-layer aerated concrete wall. We compare moisture behaviours of the steady-state and unsteady-state processes in two ways: comparison of the moisture distribution in the thickness of the enclosing structure during maximum moisture accumulation period and comparison of the average moisture of the wall during a year. It was found that the solution of the unsteady-state equation of moisture transfer gives significantly more possibilities than the solution of the steady-state equation of moisture transfer. As a result, we recommend to use the developing unsteady-state mathematical model to predict the moisture regime of enclosing structures.