The Optimum Design of Stratified Thermal Energy Storage Systems—Part I: Development of the Basic Analytical Model

Abstract

This investigation employs the techniques of second law analysis to show that significant improvements in performance are possible through the use of “perfectly stratified” thermal energy storage systems. Although the possibility of such improvements has been widely acknowledged in the literature, previous studies have not quantified the maximum possible performance gains attainable through the use of thermally stratified systems, nor have they established the viability of these optimal systems in actual practice. Thus, the present study was performed to achieve these two goals. This work is presented in two parts. In Part I, the specific class of systems to be examined is defined and the development of the basic analytical model is carried out. The completion of the analytical model and the presentation and interpretation of the results of an optimization study are given in Part II.