In order to more accurately estimate the reserves of underground gas storage under the complex operation mode of multi-period strong injection and strong production, and design a reasonable allocation scheme of injection and production gas volume. In this paper, the material balance equation is improved according to the “hollow square” shape characteristics of apparent bottom hole flow pressure and cumulative production of multi-cycle injection-production wells in gas storage. Combined with the node analysis method, a new evaluation method of multi-period reserves and injection-production capacity of underground gas storage is established by using the vertical pipe flow equation, erosion flow equation, critical liquid carrying flow equation and critical sand flow equation to constrain the gas inflow and outflow equations respectively. Then, taking the gas storage as a case, the method is compared with the field data. The results show that this method avoids the inconsistency of the existing methods in solving the reserves of underground gas storage, and provides a more scientific and relatively reliable method for reserves and capacity prediction.
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