In order to explore the influence of working parameters on the leakage characteristics of carbon ring seals with different shaft diameters under the turbulent flow effect,a theoretical model of turbulent dynamic lubrication was established based on the research of laminar dynamic lubrication.By selecting the Ng-Pan turbulence coefficient expression,the iterative solution of control equation of the medium fluid pressure was carried out by finite difference method,and the leakage characteristics of the carbon ring seal was analyzed.The results show that the dynamic pressure effect of the carbon ring seal is more prominent in the turbulent flow state,and its sealing performance in the turbulent flow state is worse than that in the laminar flow state.With the increase of the rotational speed,the maximum pressure value of the flow field of the two flow regimes increases in a nonlinear divergent manner,while the leakage rate increases as a whole but slowly.With the increase of inlet pressure,the maximum pressure of the flow field increases linearly and convergently under the two flow regimes,while the leakage rate increases approximately in a relatively parallel linear trend.With the increase of eccentricity,the maximum pressure of the flow field increases exponentially under the two flow regimes,and the leakage rate increases nonlinearly.Under the condition of large shaft diameter,it is closer to the actual flow state when considering turbulence effect.