Transwall modelling using effective conductivities

A finite difference solution to the Fourier conduction equation, using effective conductivities, has been applied to a transwall module, and its accuracy has been verified by experiment. The method forms the basis of a computer program which was used to compare the thermal performance of a water-dye filled module with one of similar size filled with a water-gel solution and incorporating a sheet of high absorption solar glass. The former gives a 30% greater heat release over the evening period. The model shows that energy saving of 23% and 62% can be achieved for a transwall installed in a house sited in the West of Scotland and in the South of France, respectively.