Abstract
In the case of condensation problems from the standpoint of prevention of condensation damage, it is fundamentaly necessary to forecast the distribution of moisture content in building walls. But it has been seen that the theory of simultaneous heat and moisture transfer in materials had never been fully established because of the complexity of the transfer mechanism and the difficulty of determining transfer coefficients and of performance of detailed experiments. Our purpose in this paper is to establish the equation which can predict the process of condensation. The results investigated in Part 1 of this paper can be summarized as follows. (1) Based on the fundamental equations of heat, water vapour and water liquid transfer in materials, the simultaneous heat and moisture transfer equations to be investigated were presented. (2) The principles of determination and the measuring methods suitable for building materials for all transfer coefficients contained in the equations were clarified. (3) The new method of separation of moisture conductivity, which was one of transfer coefficients, into vapour and liquid components was proposed. (4) Based on the measuring methods, all transfer coefficients were measured for soft wood fibreboard as a building material.
