The low heat conductivity of the phase change material directly decreases the heat transfer efficiency of the phase change heat exchanger. To solve this problem

the structure of the heat exchanger was improved. Four arrangement methods were applied to optimize the phase change regenerator and carry out numerical simulation

namely the triangular inline

the concentric circles

the square inline and the square misalignment. The simulation results show that

the melting time required for phase change material in the heat exchanger using square inline and square misalignment arrangement is the same

and that for the concentric arrangement is the shortest. With the triangular inline

square inline and square misalignment arrangement

dead zone will appear at later stage of the heat storage

which prolongs the time required for melting of the phase change material

and the melting time increases by 57.20%

26.47% and 26.48%

respectively

compared with the concentric arrangement.