The present study deals with the investigation of melting phenomena in single vertical shell-and-tube latent heat thermal energy storage unit. A two dimensional axi-symmetric computational fluid dynamics model based on the enthalpy-porosity method was developed to investigate the melting behaviour. Organic alkane n-eicosane and n-eicosane/graphene nanosheets with different volume fractions were considered as the phase change materials (PCMs). Water was considered as the heat transfer fluid (HTF) flowing inside the tube and the PCM is filled in the shell side of thermal energy storage unit. A variety of numerical simulations were performed for different heat transfer fluid inlet temperatures and varying loadings of graphene nanosheets. Numerical calculations show that higher inlet temperature of the heat transfer fluid decreases the melting time due to accelerated natural convection. We also show that the inclusion of graphene nanosheets significantly decreases the melting time due to the enhanced thermal conductivity of PCM. At 2 vol% graphene laoding, melting time reduces significantly by ∼41% when the HTF temperature is 60 °C and ∼37% when the HTF temperature is 70 °C.
|Number of pages||13|
|Journal||Applied Thermal Engineering|
|Publication status||Published - Aug 25 2016|
All Science Journal Classification (ASJC) codes
- Energy Engineering and Power Technology
- Industrial and Manufacturing Engineering