Research PaperComparison of two numerical heat transfer models for phase change material board

- Two numerical heat transfer models for PCM board was compared.
- The effective heat capacity model had inevitable calculation error.
- The effective heat capacity model with small phase change temperature range had large error.
- The effective heat capacity model needed less computing time than the enthalpy model.

The effective heat capacity method and the enthalpy method are the two most common methods to build the numerical heat transfer models for phase change material (PCM) board. The objective of this research was to compare the PCM heat transfer models which were built by the effective heat capacity method and the enthalpy method respectively. Based on the numerical results of these two models, it was found that when the model was built with the effective heat capacity method, the calculation error was inevitable when the state (solid, molten or liquid) of PCM was changed during the calculation of one time step, while there was no such error when the model was built with the enthalpy method. The phase change temperature range could affect the magnitude of the calculation error when the model was built with the effective heat capacity method. When the phase change temperature range was very small, the calculation error of the model with the effective heat capacity method could be significant. However, the model with the effective heat capacity method needed less computing time than the model with the enthalpy method.