Packed bed thermal energy storage model – Generalized approach and experimental validation

•A general heterogeneous lumped-element model of heat transfer in packed beds is developed.•The proposed model expands the application range of existing models.•Its applicability to different configurations of packed beds is shown.•The implementation in Modelica favors an easy integration as a sub-model within bigger plant models.

Packed beds serve as thermal energy storages (TES) and heat exchangers (HEX) in different technological applications. In this paper, a general heterogeneous model of heat transfer in packed beds is developed. It is implemented by lumped element formulation in object-oriented modeling language Modelica and is successful validated with data sets taken from two different experiments reported in literature.The main advantages of the introduced model are the general, theory-based approach and the lumped element formulation in Modelica. The first point mentioned above should allow to simulate a packed bed TES/HEX without the necessity applying measured data for model calibration or to apply specific heat transfer correlations with restricted application. The second point establishes the possibility to integrate the TES/HEX model within plant models of larger scale without increasing the simulation time drastically.