Influence of slip effects and flow regimes on the sealing performance of diamond cross-section groove dry gas seals

Purpose A novel diamond cross-section groove design inspired by the structural features of diamond cross-sections is proposed to optimize the performance of dry gas seals. Design/methodology/approach The groove geometry imitates diamond-like hydrodynamics, effectively guiding flow, suppressing turbulence and reducing pressure loss. Three-dimensional numerical simulations using ANSYS were conducted to evaluate flow field characteristics and sealing behavior under various operating conditions. Findings The results show that the diamond grooves generate stable vortices and strengthen hydrodynamic pressure in the gas film. Their symmetric structure provides load capacity in both rotational directions, overcoming the limitation of conventional spiral grooves under reverse operation. At high rotational speeds, the geometry stabilizes the flow field, suppresses turbulence and pressure fluctuations and achieves a microscale self-sealing effect, thereby reducing leakage. Turbulence increases the opening force by about 12%, while slip effects reduces it by about 5%, with the most significant effect under laminar flow. Leakage increases markedly with large film thickness, with turbulence combined with slip effects producing values nearly 50% higher than laminar flow, indicating a strong coupling between microscale gas dynamics and macroscopic flow. Frictional torque is about 15% higher in turbulence compared to laminar flow, whereas slip effects reduces it by about 10%, reflecting multiscale regulatory effects. Originality/value These findings provide an effective pathway for achieving efficient, low-leakage and low-friction design optimization of dry gas seals.