Developing mass transfer based model for predicting VOCs emission from building materials.

摘要

Building interior materials have been identified as significant indoor VOC (Volatile Organic Compounds) sources, which can affect indoor air quality significantly. This study focuses on developing mass-transfer-based model that can be used to predict VOC emissions from building materials at their actual use conditions, and determining parameters required for applying the model as well.; A simplified yet physically-based model was developed to predict VOCs emissions from wet materials like paints. Locally bought water-based emulsion paint was tested in the Field and Laboratory Emission Cell (FLEC). Experimental results are found to agree well with the model predictions.; FLEC is used to inversely determine the diffusion and sorption coefficients required for dry building materials. The inverse parameter estimation method developed allows accurate determination of several parameters simultaneously. The method is validated regarding the uniqueness, stability and accuracy by using synthetically generated series-of-measurements.; An inverse function estimation method - conjugate method of minimization with the adjoint problem, in conjunction with an environmental chamber or the non-destructive test facility - FLEC, was developed to figure out the VOCs' initial condition within the dry building material. The proposed method can be non-destructive to the test material if using FLEC and the distribution obtained is in a continuous form.; A comprehensive IAQ model was developed in this study which takes various conditions into consideration and thus can handle different building scenarios. Currently, the model can deal with different ventilation modes, multi-component and multi-layer material, porous/non-porous materials, non-uniform initial VOCs distributions, and transient outdoor air VOCs concentration. It can be used as a decision-making tool for assessing the impact of material emissions on indoor air quality under various ventilation conditions.