Heat Transfer Enhancement of Latent Heat Storage Using Novel Quadruple Helical Fins

A novel fin configuration which is of quadruple helical geometry is proposed to augment the heat transfer performance of latent heat thermal energy storage systems. The thermal characteristics of paraffin wax under the influence of quadruple helical fins and longitudinal fins are analyzed through three-dimensional numerical formulation employing enthalpy-porosity approach. The impact of these two fin geometries on the natural convection during melting is also investigated. The numerical results are validated against experimental results. The quadruple helical fins are found to be superior to conventional longitudinal fins in accelerating phase change rates as they provide higher heat transfer surface despite occupying same volume. Hence, the melting time was reduced by 85% with quadruple helical fins as compared to system without fins and longitudinal fins could exhibit 80% reduction in melting time. The reduction in solidification time is found to be 68% (quadruple fins) and 63% (longitudinal fins). Further, quadruple fin arrangement can generate vortex flow in liquid phase change material during melting and hence, enhanced natural convection is observed when compared to longitudinal fin system. The role of heat transfer fluid in altering the phase change rate is pronounced only in the finned systems.