Characterization of Transient Temperature Field in Underground High-Pressure Gas Storage Structures

In order to deeply study the characteristics of transient temperature field changes in underground high-pressure gas storage structures under the action of air pressure and temperature cycles. Based on the thermodynamic control equations, the curves of gas pressure and temperature changes in the reservoir are derived, and the influence of contact thermal resistance at the steel liner-concrete interface on the heat transfer process is analyzed. On this basis, the evolution of the temperature field of the gas storage structure under single-cycle and multiple-cycle conditions was further explored. It was found that: The temperature change of the gas storage structure showed significant fluctuation, especially near the surface of the cavern, where the temperature fluctuation was particularly significant. With the increase of the number of temperature loading cycles, the heat is gradually accumulated, and the structural temperature field reaches the dynamic equilibrium state after about 15 cycles; while the temperature fluctuation phenomenon and the heat accumulation effect are not obvious in the surrounding rock area which is more than 3 meter away from the surface of the cavern.