Computer models for analyzing heat transfer have been developed for the thermal analysis of a self-regulating heating floor. Self-regulation is due to the conductive polymer composite cables: they are good conductors at low temperatures, and electrical insulators when the temperature increases. The first calculations, with a two dimensional finite element code, were performed on a piece (one meter square) of heating floating floor made of high density fibre board, under which self-regulating heating cables were placed. The diffusive effect of the aluminium sheet placed between the cables and fibre board is shown. Different widths and thicknesses were tested. Results of the surface temperature are in good agreement with experimentation. In the second phase, a finite element modelling of the thermo-mechanical behaviour of the self-regulating heating floor, installed in a room, was carried out. Simulations were compared to experimentation. The room wall temperature was regulated: temperature measurements were performed, in particular, between the floor and the ceiling. Heat fluxes exchanged between the floor, the walls and the ceiling were introduced into the model and turbulent convection was modelled by equivalent conductivity. We took into account a turbulent boundary layer of air on the floor. Similar computed and measured temperatures were obtained. An interesting result is the effect of a supplementary energy source (like energy supplied by the sun) on the floor―a decrease in the calculated consumed energy by the cables, due to the local increase in temperature of the cables, is exhibited.
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