Underground hydrogen storage (UHS) and compressed air energy storage (CAES) are two viable large-scale energy storage technologies for mitigating the intermittency of wind and solar power. Therefore, it is meaningful to compare the properties of hydrogen and air with typical thermodynamic storage processes. This study employs a multi-physical coupling model to compare the operations of CAES and UHS, integrating gas thermodynamics within caverns, thermal conduction, and mechanical deformation around rock caverns. Gas thermodynamic responses are validated using additional simulations and the field test data. Temperature and pressure variations of air and hydrogen within rock caverns exhibit similarities under both adiabatic and diabatic simulation modes. Hydrogen reaches higher temperature and pressure following gas charging stage compared to air, and the ideal gas assumption may lead to overestimation of gas temperature and pressure. Unlike steel lining of CAES, the sealing layer (fibre-reinforced plastic FRP) in UHS is prone to deformation but can effectively mitigates stress in the sealing layer. In CAES, the first principal stress on the surface of the sealing layer and concrete lining is tensile stress, whereas UHS exhibits compressive stress in the same areas. Our present research can provide references for the selection of energy storage methods.

中文翻译：

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衬砌岩洞地下储氢与压缩空气储能热力学和力学响应对比分析


地下储氢（UHS）和压缩空气储能（CAES）是两种可行的大规模储能技术，用于缓解风能和太阳能的间歇性。因此，将氢气和空气的特性与典型的热力学存储过程进行比较是有意义的。本研究采用多物理耦合模型来比较 CAES 和 UHS 的操作，整合了洞穴内的气体热力学、热传导和岩石洞穴周围的机械变形。使用额外的模拟和现场测试数据来验证气体热力学响应。岩洞内空气和氢气的温度和压力变化在绝热和非绝热模拟模式下表现出相似性。与空气相比，氢气在充气阶段后达到更高的温度和压力，理想气体假设可能会导致对气体温度和压力的高估。与CAES的钢衬里不同，UHS的密封层（纤维增强塑料FRP）容易变形，但可以有效减轻密封层的应力。在CAES中，密封层和混凝土衬砌表面上的第一主应力是拉应力，而UHS在相同区域表现出压应力。我们目前的研究可为储能方法的选择提供参考。