Numerical simulation on the thermal performance of hydraulic floor heating system with phase change materials

A two-dimensional coupled heat transfer model based on variable thermophysical parameters of PCM is established from the building with phase change thermal storage structure in this paper. The results show that the thermal conductivity of PCM plays a central role in maintaining air temperature during the PCM solidification. Comparison between the effects of PCM floors and concrete floors on indoor temperatures shows that the air temperature fluctuation in the cavity with PCM structure is in a smaller magnitude, and the temperature control system is relatively simple. Moreover, improving the thermal conductivity of PCM can accelerate thermal diffusion rate, reduce thermal inertia and shorten the storage time of the heating system. A new floor heat storage structure to accelerate the air temperature rise in the cavity is proposed, and an empirical correlation between the phase change temperature and the air temperature in the cavity is also presented.