Research On The Influence Of Spiral Groove Position On Steady-state Performance Of Gas Film Seal

Cylindrical gas film seal technology has always been an important research direction in the field of aviation gas turbine seal.With the continuous innovation and development of modern science and technology,the research of cylindrical gas film seals has gradually deepened.Considering that the slotting structure of the static ring in the cylindrical gas film seal pair is difficult to process in practice,the slotting structure on the moving ring is considered instead.A structure of slotting on the moving ring has been built,and compared with non-groove model and static ring grooving model through the simulation results.Based on the steady-state performance of the gas film under different operating and structural parameters,the steady-state sealing performance of the three gas film models was compared from two aspects of theoretical calculation and numerical simulation.The Reynolds equation was solved numerically by the central difference method.The formulas for calculating the steady-state performance of gas film has been introduced,such as leakage,film reaction,film stiffness and friction torque.Based on the principle of control variable method,three operating parameters and two structural parameters were changed to simulate the steady-state sealing performance of the gas film model.In the light of the static pressure distribution drawing,shear stress distribution drawing and gas particle trajectory drawing obtained from the simulation of the three models,three models were compared and analyzed in theory and simulation combined with hydrodynamic lubrication theory.The results show that the hydrodynamic pressure effect of the two grooved models is better than that of the non-grooved model,while the hydrodynamic pressure effect of the static grooved film model and the dynamic grooved film model is almost the same,which shows that the steady-state sealing performance of the grooved film model is better than that of the non-grooved model.In order to further compare the steady-state sealing characteristics of the two grooved models,the sealing performance parameters of the two grooved models were studied in depth.The results show that the position of spiral grooves have a certain influence on sealing performance.The sealing performance of two grooved models has their own advantages and disadvantages,which is determined by different working conditions.The operating parameters and structural parameters both have significant effects on the steady-state sealing characteristics of the gas film model.The hydrodynamic pressure effects and steady-state performance of three models under different operating parameters were systematically expounded,which lays a foundation for slotting method,steady-state sealing performance,engineering application and practical production and processing of cylindrical gas film seals in the future.