Modeling of a Solid/Liquid Thermal Storage System

A computational model utilizing the finite difference method was developed to simulate the behavior of a simple thermal storage system. The system analyzed utilizes the deposition of heat from a fluid to a solid matrix in the initial part of cycle followed by heat removal in the latter part. The storage system was divided into perpendicular slices with respect to the direction of the heat transfer fluid (HTF) flow. To further reduce the area of the slice on which the calculations were performed, the symmetry of the design was then used. Two dimensional conduction and convection calculations were performed within the plane generated by each slice. Interaction between the slices was limited to only the HTF flow rate. It was assumed that the system would experience no losses to the ambient and the HTF contained in each slice would be fully mixed. First and Second Law analysis were incorporated as a means of evaluating different configurations of the storage system design. A technique that allows the designer to choose between design options is discussed.