THERMAL-ENERGY STORAGE - DYNAMIC PERFORMANCE-CHARACTERISTICS OF CANS EACH CONTAINING A PHASE-CHANGE MATERIAL, ASSEMBLED AS A PACKED-BED

The transient behaviour of a latent-heat thermal-energy store has been measured experimentally and predicted via a computer model Experimental results obtained from temperature-step input tests for this packed-bed store, incorporating a phase-change material (MgCl26H2O), which was encapsulated in metal cans, are presented. Film-side heat-transfer coefficients appropriate to the thermal charge and discharge modes for wide ranges of Reynolds number and swing temperature have been deduced The variations of the overall heat-transfer coefficient (with time) as well as its mean integrated value has been obtained. A non-dimensional heat-transfer parameter describing the behaviour of the packed-bed, namely the Goncalves number, is introduced and a mean integrated value for it determined in order to characterise the thermal response of the energy store. Predicted dynamic performances, obtained via computer simulations, have been corroborated to within experimental error, by observations.