压气储能地下储气库压缩湿空气热力学模型

A thermodynamic model of compressed humid air within an underground rock cavern for compressed air energy storage

为了解地下储气库内的湿度变化过程及其对压缩空气热力学过程的影响,基于压缩空气热力学理论,分析了水蒸气的相变传热机理,提出了考虑空气湿度因子影响的压缩空气热力学模型,并进行了验证。通过算例,分析了湿度变化对压缩空气压力与温度变化规律的影响以及储气库冷凝与蒸发效应。研究结果表明,入库气体含湿量大小对储气库压缩空气的压力影响较弱,对压缩空气的温度影响较为显著。在放气阶段,储气库内的相对湿度逐渐升高,并有可能达到100%,从而产生冷凝现象;在充气阶段,储气库内的相对湿度逐渐降低,并将产生蒸发现象。储气库内的冷凝水量总体上大于蒸发量。工程设计时,应关注储气库长期运行后的冷凝水处理问题。

For understanding the variation process of humidity in an underground cavern for compressed air storage and its influence on the thermodynamic processes of compressed air,the heat transfer mechanisms of vapor phase change were analyzed.A thermodynamic model for compressed air taking the humidity of air into account was suggested and validated.The influence of humidity variation on the temperature and pressure of compressed air and condensation and evaporation effects in the cavern were analyzed.The results show that vapor quantity included in inflowing compressed air has a significant influence on temperature variation but only a slight influence on pressure variation of the compressed air in the cavern.During compressed air discharge,relative humidity in the cavern rises gradually and could go up to 100%,and condensation happens.During air charging,relative humidity in the cavern decreases gradually,and evaporation occurs.The quantity of condensed water is far greater than that of evaporated water.The problem of water treatment after the cavern experienced a long-term operation should be considered in engineering designs.