Heat transfer performance and structural optimization design method of vertical phase change thermal energy storage device

• The heat transfer model describing the vertical phase change thermal energy storage device (VPCTESD) had been developed.
• This paper proposes the optimization design parameters of VPCTESD with experiment, theoretical analysis and numerical simulation methods.
• The measured results of application case shows that the developed mathematical model of VPCTESD in this study is applicable and the designed VPCTESD has a good flow and thermal performance.
• The efficiency of heat discharge is about 93%.

This research aims to further improve the thermal performance and the heat charge and discharge efficiency of the developed vertical phase change thermal energy storage device (VPCTESD) in order to adapt the application of VPCTESD in solar energy utilization technology and waste heat utilization technology. Based on the developed heat transfer model of VPCTESD, with experiment and numerical simulation methods, this paper proposes the optimization design parameters of VPCTESD filled with PCMs (called DX-53), including the gap between DX-53 slabs, the velocity of HTF (water) in heat transfer unit's flow passage, the thickness of DX-53, the filling height of DX-53 and divergent length of entrance region. The research result provides the reference methods for evaluation of the thermal performance of VPCTESD.