A Comparison of Radial-flow and Axial-flow Packed Beds for Thermal Energy Storage

A thermal energy storage system where heat is transferred to a cylindrical packed bed along the radial coordinate is described. The governing energy equations and various mechanisms that cause exergetic losses are discussed. The radial-flow packed bed is compared to a dimensionally similar axial-flow packed bed. A multi-objective optimisation of radial-flow and axial-flow stores indicates that radial-flow stores have a comparable performance, but that the additional volume required for by-pass flows leads to higher capital costs