A new mass transfer based model of VOV emissions from building materials

A new generally applicable model for calculating the surface emissions of VOCs (volatile organic compounds) from building materials and the VOC instantaneous distributions in the materials is developed. Different from the mass transferbased models in the literature, it doesnt neglect the mass transfer resistance through the air phase boundary layer. Results obtained by using the presented model are validated with experiments from the literature. By normalizing the model, the
factors of influencing the surface emissions of VOCs from building material are clarified and the influences are quantitatively analyzed. It is found that the dimensionless emission rate of VOCs is the function of Bim (the Biot number for mass transfer) / K (the partition coefficient) and Fom (the Fourier
number for mass transfer), which summarizes the general surface emission characteristics of VOCs from building materials and provides the basis for fitting experimental data to formulate empirical correlations of VOC emissions. Based upon the model and the analysis, the applicable condition of
the famous Little model is presented.