The　latent　heat　thermal　energy　storage　device　provides　an　alternative　solution　to　the　problem　of　imbalance　between　energy　supply　and　demand.　To　enhance　heat　transfer,　a　series　of　latent　heat　thermal　energy　storage　devices　with　novel　concentric　annular　fins　are　proposed,　as　the　design　accelerates　the　melting　and　solidification　processes　of　stearic　acid.　Based　on　the　finite　volume　method,　the　enthalpy-porosity　approach　is　employed　to　numerical　simulation　the　charging/discharging　process.　Effects　of　the　number　and　arrangement　of　concentric　annular　fins　on　the　liquid　fraction,　melting　and　solidification　front,　melting　uniformity,　temperature　uniformity,　velocity　uniformity　and　total　melting　and　solidification　time　during　melting　and　solidification　are　studied.　Results　showed　that　the　melting　and　solidification　rate　increases　with　increasing　fin　number.　The　total　melting　and　solidification　times　were　reduced　by　72.83%　and　86.39%,　respectively,　for　the　case　with　9　concentric　annular　fins　compared　to　the　bare　tube.　Both　melting　performance　and　temperature　uniformity　were　improved.　Further,　the　effect　of　fin　arrangement　on　the　melting　and　solidification　performance　was　investigated　with　the　same　total　volume　of　fins.　Results　revealed　that　the　heat　transfer　performance　of　progressively　shorter　fin　structures　＜　uniformly　distributed　fins　＜　progressively　longer　fins　＜　performance　of　non-uniformly　distributed　fin　arrangement.　The　non-uniform　fin　arrangement　reduces　the　total　melting　and　solidification　time　of　stearic　acid　by　85.46%　and　90.11%,　respectively,　compared　to　bare　tube.　This　work　provides　new　insights　into　the　understandings　of　the　transient　phase　change　process　and　the　strategies　for　guiding　the　design　for　thermal　energy　storage　devices　using　annular　fins.