Reducing uncertainties in the numerical simulation of melting processes in phase change materials by a systematic model analysis using temperature dependent material properties

• Applicant: Professor Dr.-Ing. Dieter Brüggemann
• Subject Area: Technical Thermodynamics
• Term: from 2017 to 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 338765414

Latent thermal energy storages (LTES) with solid/liquid phase change are attractive for storing thermal energy at low temperature differences. More and more simulations methods are used to assist in the design of these storages. Although some of the underlying models have been developed a long time ago, they are still insufficiently validated. Therefore, in the first years of the project, the melting process in a simple geometry was examined and validated in detail. It turned out that the thermophysical properties, which vary largely in the literature, were responsible for the deviation between numerical and experimental results. In contrast, the use of average temperature-dependent thermophysical properties led to an agreement within 5 to 10 % between numerical and experimental results. Since this is sufficient for a technical system, we focus on the transfer of the results to technical applications.Hence, this project aims to demonstrate through experiments and simulations how strongly the input parameters influence the design of these storages.

• DFG Programme: Research Grants