FIGURES OF MERIT FOR HYBRID THERMAL ENERGY STORAGE UNITS

Two figures of merit for hybrid Thermal Energy Storage (TES) units are developed: the volumetric figure of merit, V ~ , and the temperature control figure of merit, T ~ ∆ . A dimensional analysis shows that these quantities are related to the performance specification of the storage unit and its physical design. A previously benchmarked semi-empirical finite volume model is used to study the characteristics of various plate-type TES-unit designs. A parametric study is used to create a database of optimal designs, which is then used to form simple correlations of V ~ and T ~ ∆ in terms of design requirements and attributes. A preliminary design procedure utilizing these figures of merit is suggested. Sample calculations show that these correlations can be used to quickly determine the design attributes of a plate-type TES-unit, given design requirements.