Two scale model for predicting the voc diffusion coefficient in porous building materials

Based on the micro structure analysis of building material and mercury intruding porosimetry tests, a macro-meso two scale model for predicting the diffusion coefficient of volatile organic compounds (VOCs) is proposed. Different from traditional model for diffusion coefficient in the literature, the present model not only considers the porosity, but also considers the pore size distribution and pore connection modes. Emission experiments for three kinds of medium-density boards indicate that the calculated results from the present model agree much better with the experimental results than the traditional model in the literature.