The thermal-fluid-structure interaction coupling method is adopted in this paper to analyze the sealing performance of spiral-grooved dry gas seal. Effect of grooved ring rotation on sealing performance is discussed in detail. The real gas model is applied to obtain the accurate sealing performance under different inlet temperature and pressure with air and SCO2 as working fluid respectively, which provides a vital reference for SCO2 seal application. The results obtained with the thermal-fluid-structure interaction coupling method are reliable. It is found that grooved ring rotation has a significant influence on sealing performance especially for large film thickness. The pressure and temperature of the model which is grooved on the rotating ring are higher than those of the model which is grooved on the stationary ring, but the open force and leakage are opposite. In addition, SCO2 model and air model show a significant difference on the sealing performance and the sealing performance of SCO2 model is easier to be affected by the inlet temperature and pressure compared with air model. (C) 2018 Elsevier Ltd. All rights reserved.