Abstract: To mitigate the impact of renewable energy on the stable operation of power grids, the development of energy storage systems is necessary. Compressed air energy storage, as a large-scale long-duration energy storage system, has attracted widespread attention. In tunnel-type artificial caverns, heat exchange between the gas at the cavern end and the incoming cold airflow is limited during inflation. Consequently, the air temperature increases rapidly during pressurization, producing a pronounced temperature gradient between the inlet and the cavern end. The excessively high temperature affects the durability of the sealing materials at the end of the cavern, which is detrimental to the force-bearing of the sealing structure, necessitating the adoption of necessary temperature control measures. Based on the Bernoulli effect, this paper proposes a scheme to add a temperature control pipe at the central axis position of the cavern. By adjusting the airflow lines within the cavern, the mixing between incoming air and the existing air is enhanced, thereby promoting internal air circulation within the cavern. After optimizing the parameters of the temperature control scheme, the temperature difference within the cavern can be effectively reduced. The results show that the optimized scheme can keep the temperature difference within the underground cavern below 80 ℃, which has high practical value and research and development potential.

Key words: compressed air energy storage, artificial caverns, temperature control scheme, computational fluid dynamics