Exploration of thermo-fluid-heat transfer evolution in salt cavern compressed air energy storage system under high-frequency injection and production conditions

Salt cavern compressed air energy storage (CAES) is an efficient, flexible, and large-scale clean energy storage technology. This study analyzed the thermo-fluid-heat transfer coupling behavior of the salt cavern CAES system under high-frequency injection and production conditions and explored the dynamic evolution of thermodynamic parameters between the gas and surrounding rock. The results show that during injection and production cycles, gas pressure and temperature exhibit a periodic trend of rising and falling. When the injection temperature increases, gas pressure, temperature, and wall temperature rise correspondingly, while increased injection pressure has the opposite effect. High injection and production mass flow rates improve energy storage efficiency but exacerbate thermal effects and system fluctuations. Variations in surrounding rock thermal conductivity and surface heat transfer coefficients lead to crossing patterns: low thermal conductivity and low heat transfer coefficients enhance gas temperature rise but intensify thermal stress. Optimizing injection and production strategies and thermal parameters is key to ensuring long-term system stability and operational efficiency. This study provides theoretical support for the design and optimization of salt cavern CAES system and offers technical assurance for the efficient utilization of clean energy.