Heat Transfer with Phase Change in a Multilayer Construction: Simulation versus Experiment

Abstract

The latent heat storage in the layer of phase change material (PCM) exposed to dynamic changes in boundary temperature was investigated numerically and experimentally. The original numerical model of heat transfer with phase change using a mushy volume approach was proposed and validated. The main improvement in the proposed model in comparison to others is that the compaction of the mesh and longitude of the time step were chosen after analysis of its impact in the field of error. The model was tested in the case of thin layer structure of the triple glazing window with one cavity filled with phase change material paraffin RT18HC. The experimental validation was carried out in the climatic chamber under dynamic changes in external temperature (from 10 to 50 °C) in a daily cycle. The highest accuracy was obtained for space discretization of the control volume 1 mm thick (12 CV for 12 mm of PCM layer) and 5 min time step. The obtained RMSE values, although they cannot be directly compared because of the very different approaches to the simulations, show that the proposed algorithm is sufficiently accurate for the assessment of energy storage in the PCM window. Both the simulation and experiment proved that, under specific conditions, implementation of the PCM into the structure resulted in delaying the peak for around 4 h.