Based on the analysis of circumferential seal conditions

a three-dimensional multi-physics coupling simulation model of flow field

temperature field and structural field was established. The correctness of the model was verified by comparing the results of the thermal-fluid-structure coupling method with the theoretical model and the experimental results. The characteristics of flow field

temperature field and structure field of circumferential seal

and the distribution of von Mises stress and deformation in multi-physics coupling field were analyzed

and the effect of typical condition parameters on the performance of circumferential seal was obtained. The results showed that the pressure in the flow field decreased along the negative directim of z axis

and the pressure drop gradient was negatively correlated with the seal dam width. The seal gas generated irregular vortex motion

and the flow velocity decreased along the radial direction. The temperature field was uniformly distributed

and the maximum temperature was located at the lap joint. It was found that the maximum deformation and maximum von Mises stress were located at the convex lap joint by static structural analysis. The maximum deformation of the seal ring under thermal-fluid-structure coupling was 161% higher than that of the fluid-structure coupling and 09% smaller than that of the thermal-structure coupling

and the temperature field had a significant effect on the deformation of the seal ring. The maximum von Mises stress shifted to the transition between the seal dam and the lap joint

83% higher than that under the fluid-structure coupling and 23% higher than that under the thermal-structure coupling; and both the flow field and temperature field had great influence on the von Mises stress of the seal ring. The change of seal temperature difference plays an important role in the deformation. The change of seal pressure difference plays a major role in the maximum von Mises stress and a decisive role in the leakage.