Development of a metho d for finding a moisture diffusion co efficient
AbstractIn connection with the advent of new building materials, it b ecomes necessary to determinethe thermophysical characteristics of materials. The aim of the work is to develop metho ds forsolving the inverse problems of non-destructive testing materials. The development of metho dsand verification of its reliability is scientifically and practically imp ortant. Research metho dologiesare development of a metho d, numerical calculations and comparison of results with exp erimentaldata. Systems of nonlinear differential equations with partial derivatives of heat and mass transferare considered. The b oundary conditions are set taking into account the physics of the pro cessas much as p ossible. As an additional condition, the measured values of moisture and heat atthe accessible b oundary of the region are taken. The system under consideration is written in adimensionless form. First, an auxiliary task is constructed. Conjugate problem derives from it.The problem is solved by using iterative metho d. On the basis of system of equations of heat andmoisture transfer it was develop ed an approximate metho d for finding the desired value. A softwarepro duct is created and numerical calculations are carried out. The result obtained is comparedwith exp erimental data of other scientists.The comparison shows a go o d agreement b etween theresults
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