Development and experimental validation of a one-dimensional dynamic hygrothermal modeling based on air humidity ratio

Abstract

A modified one-dimensional transient hygrothermal model for multilayer wall was proposed using air humidity ratio and temperature as the driving potentials. The solution for the governing equations was obtained numerically by implementing the finite-difference scheme. To evaluate the accuracy of the model, a test system was built up to measure relative humidity and temperature within a porous wall and compare with the prediction of the model. The prediction results have good agreement with the experimental results. For the interface close to indoor side, the maximum deviation of temperature between calculated and test data is 1.87 K, and the average deviation is 0.95 K; the maximum deviation of relative humidity is 11.4%, and the average deviation is 5.7%. For the interface close to outdoor side, the maximum deviation of temperature between prediction and measurement is 1.78 K, and the average deviation is 1.1 K; the maximum deviation of relative humidity is 9.9%, and the average deviation is 4.2%.

Keywords

transient hygrothermal modeling / air humidity ratio / modified modeling / experimental test / multilayer wall

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