Topology optimization for mass transfer enhancement in open thermochemical energy storage reactors

The mass transfer enhancement in open system thermochemical energy storage is achieved in this work through the optimal design of flow channel geometries. Such flow channel geometries aim to maximize how gas reactants are distributed to the reactive sites and are derived from the topology optimization algorithm. Two reactor configurations are analyzed, namely sieve reactors and cylindrical reactors, and the performance of the generated designs are compared with literature benchmarks. Tentacular flow channel geometries emerged, with the flow channels elongating in the reactive bed without directly connecting the inlet and outlet interfaces. In the instance of a fixed time, a +757.8 % increase in the amount of discharged energy is obtained compared to literature solutions. Besides, the optimal geometrical features differ depending on the targeted performance metric. In particular, thinner channels are found to be favourable to increasing the amount of discharged exergy compared to discharged energy. Overall, the emerging design trends define new enhancement pathways for the performance improvement of open system thermochemical energy storage reactors and significantly contribute to the technology advancement.