Coupled heat and mass transfer in concrete elements at elevated temperatures Original Research Article

Realistic simulation of the coupled heat and mass transfer in concrete elements requires detailed knowledge of the dominant transfer mechanisms. Transfer under thermal gradients implies that several transport mechanisms, such as diffusion and Darcy flow, may be simultaneously contributing to hygral transfer, depending on the local temperature and moisture content. The relevant transport processes can be described as functions of thermodynamical state variables, and incorporated into a numerical model for simulation of coupled heat and mass transfer. A set of transport coefficients has been determined, as well as experimental moisture distributions in a prestressed concrete vessel under thermal gradients. These measurements are compared with the results of a numerical simulation based on a description of physical transfer processes relevant to porous media.