Optimisation of a phase change thermal storage system

PCMs have always been viewed as a suitable candidate for off peak thermal storage, particularly for refrigeration systems, due to the high latent energy densities of these materials. However, due to the need to have them encapsulated within a container this density is reduced. Furthermore, PCMs have a low thermal conductivity which reduces the useful amount of energy which can be stored. To consider these factors, the true energy storage density of a PCM system was proposed and optimised for PCMs encapsulated in slabs. Using a validated numerical model of the system, a parametric study was undertaken to investigate the impact of the slab thickness, gap between slabs and the mass flow rate. The study showed that, when optimised, a PCM system can deliver a true energy storage density between 53% and 83% of the latent energy density of the PCM. Keyword s—Phase change material, refrigeration, sustainability, thermal energy storage.

[1]  Agis M. Papadopoulos,et al.  Perspectives of solar cooling in view of the developments in the air-conditioning sector , 2003 .

[2]  Amar M. Khudhair,et al.  A review on phase change energy storage: materials and applications , 2004 .

[3]  Graeme Maidment,et al.  A review of research concerning the use of PCMS in air conditioning and refrigeration engineering , 2002 .

[4]  F. Bruno,et al.  Maximizing the energy storage performance of phase change thermal storage systems , 2009 .

[5]  R. Velraj,et al.  Experimental investigation and numerical simulation analysis on the thermal performance of a building roof incorporating phase change material (PCM) for thermal management , 2008 .

[6]  Long Jian-you,et al.  Numerical and experimental investigation for heat transfer in triplex concentric tube with phase change material for thermal energy storage , 2008 .

[7]  S. von Dosky,et al.  Numerical simulation of a refrigeration cycle for scaling towards small geometries , 2008 .

[8]  Uroš Stritih,et al.  Experimental investigation of PCM cold storage , 2009 .

[9]  D. Morrison,et al.  Effects of phase-change energy storage on the performance of air-based and liquid-based solar heating systems , 1977 .

[10]  L. Cabeza,et al.  Heat and cold storage with PCM: An up to date introduction into basics and applications , 2008 .

[11]  Wasim Saman,et al.  Thermal Performance Of A Pcm Thermal Storage Unit , 2008 .

[12]  Jean-Pierre Bédécarrats,et al.  Phase-change thermal energy storage using spherical capsules: performance of a test plant , 1996 .

[13]  Wasim Saman,et al.  Numerical analysis of a PCM thermal storage system with varying wall temperature , 2005 .

[14]  Hisham Ettouney,et al.  Heat Transfer During Phase Change of Paraffin Wax Stored in Spherical Shells , 2005 .