The depleted gas reservoirs can serve not only as sites for CO$_2$ sequestration but also as potential spaces for hydrogen storage. However, this process remains insufficiently understood, limiting the availability of reliable technical guidance for injection operations. In this study, a mathematical model for simulating hydrogen storage in depleted gas reservoirs was developed and numerically solved. Meanwhile, the applicability was then verified through comparison with results from previous studies. Based on this model, a detailed analysis was performed to investigate the evolution of key parameters under specific injection conditions. Finally, the effects of various factors on parameters... More >