Energy storage is considered to be able to fill the gap in the energy supply due to the fluctuating energy production out of the renewables. Furthermore, energy storage is a key issue for energy efficiency and process optimization. Energy can be stored in thermal, chemical or mechanical form in technical as well as natural systems (e.g. the subsurface).
Moreover, one of the possibilities is to store thermal energy with the help of chemical reactions: thermochemical heat storage systems are charged in endothermal reactions and restored in exothermal reactions. Calcium oxide for example reacts exothermically in presence of water to Calcium hydroxide. Applied heat releases the water and restores Calcium oxide. Because of its environmental compatibility calcium is of special interest.
In collaboration with DLR (German Aerospace Center), IFK (Institute of Combustion and Power Plant Technology), ITLR (Institute of Aerospace Thermodynamics) and IES (Institute for Energy Storage) the thermochemical energy storage behavior of Calcium is analyzed in experiments and simulation. In this project, flow and transport processes as well as chemical and in experiments shown processes are to be analyzed by numerical modelling. The constitutive relations of this complex system are depicted in a multiphase system. Changes in the structural properties such as porosity and permeability have to be considered. Furthermore thermal non-equilibrium has to be investigated. Modelling shall contribute to identify their relevance.
Primarily, the experimental data serve to build the numerical model. Further on, they are applied for calibrating purposes. In the following, the data basis of the experiments is integrated step by step into the numerical model. The experimental data shall be linked to the simulation in such a way, that the developed models continue to be optimized so that the numerical models are applied to forecast the experimental results. Therefore methods of data assimilation have to be developed and applied.
M.Sc. Seitz, Gabriele
German Aerospace Center (DLR)
Institute of Combustion and Power Plant Technology (IFK)
Institute of Aerospace Thermodynamics (ITLR)
Institute of Energy Storage (IES)