TY - JOUR
TI - Heat transfer enhancement of a cascaded thermal energy storage system with various encapsulation arrangements
AU - Nagappan Beemkumar
AU - Alagappan Karthikeyan
AU - Devarajan Yuvarajan
JN - Thermal Science
PY - 2019
VL - 23
IS - 2
SP - 823
EP - 833
PT - Article
AB - Ever increasing energy demand ever encourage for new energy production and  conservation. In the present work, the cascaded latent heat solar thermal  energy storage system has been developed to deliver the heat at different  temperature limits and its performance on the improvement of heat transfer  characteristics are studied with the use of multiple PCMs with various  encapsulation arrangements. The storage system consists of three different  PCMs which have different melting temperatures such as D-mannitol,  D-sorbitol, and Paraffin wax. Each PCM is encapsulated in different materials  of spherical balls like Copper, Aluminium, and Brass. Permanent welding of  Fins, inside the encapsulated balls of type rectangular, annular and pin is  done for enhanced heat transfer. This work investigates for the best  combination of fins which may allow the highest heat transfer rate for the  least cost. It has been concluded that the transfer of energy is the highest  in the use of Copper balls for encapsulation of PCMs with the attachment of  annular fin inside the balls. With respect to Energy cost per kJ of heat  transfer, the PCMs encapsulated in Aluminium balls with annular fins may be  preferred. However in all the combinations, to gain higher efficiency of the  system proper arrangements of all system components very close to each other  is essential to the provision of perfect insulated storage tanks and the  components of the piping circuit.