Numerical modeling of volatile organic compound emissions from multi-layer dry building materials

Abstract

This paper presents a mathematical model capable of simulating VOCs emission from a multi-layer material. The analytical solutions of the concentration in the air and the emission rate are obtained by Laplace transform and are validated through experiment. The influences of parameters of multi-layer material on the emission of VOCs are investigated in detail. Results show that the inner layer may act as a sink or a source of the top layer, depending on their initial concentrations and partition coefficients. For the case of the inner layer being a source of the top layer, the top layer becomes a barrier layer, reducing the emission rate of VOCs from the source. A low diffusion coefficient and a large thickness may promote the effect of the barrier on the emission rate, which helps to maintain better air quality in an indoor environment. The present solution is a longitudinal extension of a single layer problem, while the emission from multi-source is a transverse extension of a single layer problem.