Abstract:

The control patterns of loading period in the field of underground energy storage were investigated based on a large scale multi-heat source model, and the intermittent sequence and dynamic storage modes were considered accordingly. The results indicate that the storage efficient in the period of heating is affected by the dynamic temperature field significantly which is formed by the temperature amplitude distribution, intermittent period, rest cycle in the different load distribution, while the energy diffusion in the period of energy reservation is also affected by the dynamic temperature. The controllable energy diffusion transfer method both facilities energy storage and inhibits the loss of the stored energy. The results also indicate that the semi-day intermittent mode is more effective than the full-day intermittent mode, and the shorter intermittent period is more beneficial to optimize the energy storage quantity, average temperature and maximum temperature during the energy storage. Therefore,a reasonable selection of dynamic load mode with intermittent period and temperature distribution is beneficial for efficient heat transfer and effective energy transportation in multi-heat sources system.

Key words: thermal energy engineering, underground thermal energy storage technology, intermittent time sequence, temperature variability, energy transport