STUDY ON TOPOLOGICAL OPTIMIZATION IN DRY GAS SEAL FOR IMPROVING SEALING ABILITY AND ITS FLOW VISUALIZATION
Dry gas seals are widely used for high rotating and high pressure machinery. In the design of dry gas seals, it is cardinal importance to enhance the stiffness of gas seal film for minimizing the vibration due to external excitation. However, stiffness and gas leakage quantity have trade-off relations. Moreover, those characteristics of dry-gas seals depend on groove dimension and geometry. The spiral groove geometry is widely used dry-gas seal in general. However, it is not verified that spiral groove is optimal geometry in the all cases. Therefore in this study, we have applied to multi-objective optimum design to improve on sealing characteristics and stiffness. As a result, it was calculated optimum value of seal geometry and dimension under all conditions of operation in general. Moreover, the optimized groove was discussed mechanism of improving sealing characteristics by CFD analysis, and the effectiveness of optimized groove is verified experimentally.